diff --git a/ANNOUNCE b/ANNOUNCE
index 46c15d60..0d35a595 100644
--- a/ANNOUNCE
+++ b/ANNOUNCE
@@ -1,5 +1,5 @@
 
-Libpng 1.2.1beta3 - October 27, 2001
+Libpng 1.2.1beta4 - November 7, 2001
 
 This is not intended to be a public release.  It will be replaced
 within a few weeks by a public version or by another test version.
@@ -18,6 +18,11 @@ version 1.2.1beta2 [October 25, 2001]
 version 1.2.1beta3 [October 27, 2001]
   Removed type casts from all NULLs.
   Simplified png_create_struct_2().
+version 1.2.1beta4 [November 7, 2001]
+  Revised png_create_info_struct() and png_creat_struct_2().
+  Added error message if png_write_info() was omitted.
+  Type cast NULLs appearing in function calls when _NO_PROTO or
+    PNG_TYPECAST_NULL is defined.
 
 Send comments/corrections/commendations to
 png-implement@ccrc.wustl.edu or to randeg@alum.rpi.edu
diff --git a/CHANGES b/CHANGES
index b82ec4bc..8adb246f 100644
--- a/CHANGES
+++ b/CHANGES
@@ -993,6 +993,11 @@ version 1.2.1beta2 [October 25, 2001]
 version 1.2.1beta3 [October 27, 2001]
   Removed type casts from all NULLs.
   Simplified png_create_struct_2().
+version 1.2.1beta4 [November 7, 2001]
+  Revised png_create_info_struct() and png_creat_struct_2().
+  Added error message if png_write_info() was omitted.
+  Type cast NULLs appearing in function calls when _NO_PROTO or
+    PNG_TYPECAST_NULL is defined.
 
 Send comments/corrections/commendations to
 png-implement@ccrc.wustl.edu or to randeg@alum.rpi.edu
diff --git a/INSTALL b/INSTALL
index 9b1ab8f3..92908701 100644
--- a/INSTALL
+++ b/INSTALL
@@ -1,5 +1,5 @@
 
-Installing libpng version 1.2.1beta3 - October 27, 2001
+Installing libpng version 1.2.1beta4 - November 7, 2001
 
 Before installing libpng, you must first install zlib.  zlib
 can usually be found wherever you got libpng.  zlib can be
@@ -10,7 +10,7 @@ zlib.h and zconf.h include files that correspond to the
 version of zlib that's installed.
 
 You can rename the directories that you downloaded (they
-might be called "libpng-1.2.1beta3" or "lpng109" and "zlib-1.1.3"
+might be called "libpng-1.2.1beta4" or "lpng109" and "zlib-1.1.3"
 or "zlib113") so that you have directories called "zlib" and "libpng".
 
 Your directory structure should look like this:
@@ -64,8 +64,8 @@ The files that are presently available in the scripts directory
 include
 
  makefile.std      =>  Generic UNIX makefile (cc, creates static libpng.a)
- makefile.linux    =>  Linux/ELF makefile (gcc, creates libpng.so.2.1.2.1beta3)
- makefile.gcmmx    =>  Linux/ELF makefile (gcc, creates libpng.so.2.1.2.1beta3,
+ makefile.linux    =>  Linux/ELF makefile (gcc, creates libpng.so.3.1.2.1beta4)
+ makefile.gcmmx    =>  Linux/ELF makefile (gcc, creates libpng.so.3.1.2.1beta4,
                        uses assembler code tuned for Intel MMX platform)
  makefile.gcc      =>  Generic makefile (gcc, creates static libpng.a)
  makefile.knr      =>  Archaic UNIX Makefile that converts files with
@@ -73,6 +73,7 @@ include
                        ftp://ftp.cs.wisc.edu/ghost)
  makefile.aix      =>  AIX makefile
  makefile.cygwin   =>  Cygwin/gcc makefile
+ makefile.darwin   =>  Darwin makefile
  makefile.dec      =>  DEC Alpha UNIX makefile
  makefile.hpgcc    =>  HPUX makefile using gcc
  makefile.hpux     =>  HPUX (10.20 and 11.00) makefile
@@ -82,9 +83,10 @@ include
  makefile.macosx   =>  MACOS X Makefile
  makefile.netbsd   =>  NetBSD/cc makefile, uses PNGGCCRD
  makefile.sgi      =>  Silicon Graphics IRIX makefile (cc, creates static lib)
- makefile.sggcc    =>  Silicon Graphics (gcc, creates libpng.so.2.1.2.1beta3)
+ makefile.sggcc    =>  Silicon Graphics (gcc, creates libpng.so.3.1.2.1beta4)
  makefile.sunos    =>  Sun makefile
- makefile.solaris  =>  Solaris 2.X makefile (gcc, creates libpng.so.2.1.2.1beta3)
+ makefile.solaris  =>  Solaris 2.X makefile (gcc, creates libpng.so.3.1.2.1beta4)
+ makefile.so9      =>  Solaris 9 makefile (gcc, creates libpng.so.3.1.2.1beta4)
  makefile.sco      =>  For SCO OSr5  ELF and Unixware 7 with Native cc
  makefile.mips     =>  MIPS makefile
  makefile.acorn    =>  Acorn makefile
diff --git a/LICENSE b/LICENSE
index cb2483d9..80300142 100644
--- a/LICENSE
+++ b/LICENSE
@@ -8,7 +8,7 @@ COPYRIGHT NOTICE, DISCLAIMER, and LICENSE:
 If you modify libpng you may insert additional notices immediately following
 this sentence.
 
-libpng versions 1.0.7, July 1, 2000, through 1.2.1beta3, October 27, 2001, are
+libpng versions 1.0.7, July 1, 2000, through 1.2.1beta4, November 7, 2001, are
 Copyright (c) 2000 Glenn Randers-Pehrson
 and are distributed according to the same disclaimer and license as libpng-1.0.6
 with the following individuals added to the list of Contributing Authors
@@ -99,4 +99,4 @@ certification mark of the Open Source Initiative.
 
 Glenn Randers-Pehrson
 randeg@alum.rpi.edu
-October 27, 2001
+November 7, 2001
diff --git a/README b/README
index 71203de2..20b2edb4 100644
--- a/README
+++ b/README
@@ -1,4 +1,4 @@
-README for libpng 1.2.1beta3 - October 27, 2001 (shared library 2.1)
+README for libpng 1.2.1beta4 - November 7, 2001 (shared library 2.1)
 See the note about version numbers near the top of png.h
 
 See INSTALL for instructions on how to install libpng.
@@ -187,9 +187,9 @@ Files in this distribution:
        descrip.mms      =>  VMS makefile for MMS or MMK
        makefile.std     =>  Generic UNIX makefile (cc, creates static libpng.a)
        makefile.linux   =>  Linux/ELF makefile
-                            (gcc, creates libpng.so.2.1.2.1beta3)
+                            (gcc, creates libpng.so.3.1.2.1beta4)
        makefile.gcmmx   =>  Linux/ELF makefile (gcc, creates
-                            libpng.so.2.1.2.1beta3, uses assembler code
+                            libpng.so.3.1.2.1beta4, uses assembler code
                             tuned for Intel MMX platform)
        makefile.gcc     =>  Generic makefile (gcc, creates static libpng.a)
        makefile.knr     =>  Archaic UNIX Makefile that converts files with
@@ -197,6 +197,7 @@ Files in this distribution:
                             ftp://ftp.cs.wisc.edu/ghost)
        makefile.aix     =>  AIX makefile
        makefile.cygwin  =>  Cygwin/gcc makefile
+       makefile.darwin  =>  Darwin makefile
        makefile.dec     =>  DEC Alpha UNIX makefile
        makefile.hpgcc   =>  HPUX makefile using gcc
        makefile.hpux    =>  HPUX (10.20 and 11.00) makefile
@@ -206,10 +207,12 @@ Files in this distribution:
        makefile.macosx  =>  MACOS X Makefile
        makefile.netbsd  =>  NetBSD/cc makefile, uses PNGGCCRD
        makefile.sgi     =>  Silicon Graphics IRIX (cc, creates static lib)
-       makefile.sggcc   =>  Silicon Graphics (gcc, creates libpng.so.2.1.2.1beta3)
+       makefile.sggcc   =>  Silicon Graphics (gcc, creates libpng.so.3.1.2.1beta4)
        makefile.sunos   =>  Sun makefile
        makefile.solaris =>  Solaris 2.X makefile
-                            (gcc, creates libpng.so.2.1.2.1beta3)
+                            (gcc, creates libpng.so.3.1.2.1beta4)
+       makefile.so9     =>  Solaris 9 makefile
+                            (gcc, creates libpng.so.3.1.2.1beta4)
        makefile.sco     =>  For SCO OSr5  ELF and Unixware 7 with Native cc
        makefile.mips    =>  MIPS makefile
        makefile.acorn   =>  Acorn makefile
diff --git a/Y2KINFO b/Y2KINFO
index dfa724f6..bfb49a87 100644
--- a/Y2KINFO
+++ b/Y2KINFO
@@ -1,13 +1,13 @@
    Y2K compliance in libpng:
    =========================
 
-      October 27, 2001
+      November 7, 2001
 
       Since the PNG Development group is an ad-hoc body, we can't make
       an official declaration.
 
       This is your unofficial assurance that libpng from version 0.71 and
-      upward through 1.2.1beta3 are Y2K compliant.  It is my belief that earlier
+      upward through 1.2.1beta4 are Y2K compliant.  It is my belief that earlier
       versions were also Y2K compliant.
 
       Libpng only has three year fields.  One is a 2-byte unsigned integer
diff --git a/configure b/configure
index 33f45961..4c8b8ada 100755
--- a/configure
+++ b/configure
@@ -1,5 +1,5 @@
 echo "
-  There is no \"configure\" script for Libpng-1.2.1beta3.  Instead, please
+  There is no \"configure\" script for Libpng-1.2.1beta4.  Instead, please
   copy the appropriate makefile for your system from the \"scripts\"
   directory.  Read the INSTALL file for more details.
 "
diff --git a/libpng.3 b/libpng.3
index a7a43881..b9db5169 100644
--- a/libpng.3
+++ b/libpng.3
@@ -1,6 +1,6 @@
-.TH LIBPNG 3 "October 27, 2001"
+.TH LIBPNG 3 "November 7, 2001"
 .SH NAME
-libpng \- Portable Network Graphics (PNG) Reference Library 1.2.1beta3
+libpng \- Portable Network Graphics (PNG) Reference Library 1.2.1beta4
 .SH SYNOPSIS
 \fI\fB
 
@@ -787,7 +787,7 @@ Following is a copy of the libpng.txt file that accompanies libpng.
 .SH LIBPNG.TXT
 libpng.txt - A description on how to use and modify libpng
 
- libpng version 1.2.1beta3 - October 27, 2001
+ libpng version 1.2.1beta4 - November 7, 2001
  Updated and distributed by Glenn Randers-Pehrson
  <randeg@alum.rpi.edu>
  Copyright (c) 1998-2001 Glenn Randers-Pehrson
@@ -3635,13 +3635,13 @@ application:
 
 .SH IX. Y2K Compliance in libpng
 
-October 27, 2001
+November 7, 2001
 
 Since the PNG Development group is an ad-hoc body, we can't make
 an official declaration.
 
 This is your unofficial assurance that libpng from version 0.71 and
-upward through 1.2.1beta3 are Y2K compliant.  It is my belief that earlier
+upward through 1.2.1beta4 are Y2K compliant.  It is my belief that earlier
 versions were also Y2K compliant.
 
 Libpng only has three year fields.  One is a 2-byte unsigned integer that
@@ -3761,7 +3761,7 @@ the first widely used release:
  1.2.0beta3-5         3    10200  3.1.2.0beta3-5
  1.2.0rc1             3    10200  3.1.2.0rc1
  1.2.0                3    10200  3.1.2.0
- 1.2.1beta-3          3    10201  3.1.2.1beta1-3
+ 1.2.1beta-4          3    10201  3.1.2.1beta1-4
 
 Henceforth the source version will match the shared-library minor
 and patch numbers; the shared-library major version number will be
@@ -3819,7 +3819,7 @@ possible without all of you.
 
 Thanks to Frank J. T. Wojcik for helping with the documentation.
 
-Libpng version 1.2.1beta3 - October 27, 2001:
+Libpng version 1.2.1beta4 - November 7, 2001:
 Initially created in 1995 by Guy Eric Schalnat, then of Group 42, Inc.
 Currently maintained by Glenn Randers-Pehrson (randeg@alum.rpi.edu).
 
@@ -3836,7 +3836,7 @@ included in the libpng distribution, the latter shall prevail.)
 If you modify libpng you may insert additional notices immediately following
 this sentence.
 
-libpng versions 1.0.7, July 1, 2000, through  1.2.1beta3, October 27, 2001, are
+libpng versions 1.0.7, July 1, 2000, through  1.2.1beta4, November 7, 2001, are
 Copyright (c) 2000-2001 Glenn Randers-Pehrson, and are
 distributed according to the same disclaimer and license as libpng-1.0.6
 with the following individuals added to the list of Contributing Authors
@@ -3928,7 +3928,7 @@ certification mark of the Open Source Initiative.
 
 Glenn Randers-Pehrson
 randeg@alum.rpi.edu
-October 27, 2001
+November 7, 2001
 
 .\" end of man page
 
diff --git a/libpng.txt b/libpng.txt
index 45fe99ed..6e2934f1 100644
--- a/libpng.txt
+++ b/libpng.txt
@@ -1,6 +1,6 @@
 libpng.txt - A description on how to use and modify libpng
 
- libpng version 1.2.1beta3 - October 27, 2001
+ libpng version 1.2.1beta4 - November 7, 2001
  Updated and distributed by Glenn Randers-Pehrson
  <randeg@alum.rpi.edu>
  Copyright (c) 1998-2001 Glenn Randers-Pehrson
@@ -2848,13 +2848,13 @@ application:
 
 IX. Y2K Compliance in libpng
 
-October 27, 2001
+November 7, 2001
 
 Since the PNG Development group is an ad-hoc body, we can't make
 an official declaration.
 
 This is your unofficial assurance that libpng from version 0.71 and
-upward through 1.2.1beta3 are Y2K compliant.  It is my belief that earlier
+upward through 1.2.1beta4 are Y2K compliant.  It is my belief that earlier
 versions were also Y2K compliant.
 
 Libpng only has three year fields.  One is a 2-byte unsigned integer that
diff --git a/libpngpf.3 b/libpngpf.3
index c4d5192a..34f66002 100644
--- a/libpngpf.3
+++ b/libpngpf.3
@@ -1,6 +1,6 @@
-.TH LIBPNGPF 3 "October 27, 2001"
+.TH LIBPNGPF 3 "November 7, 2001"
 .SH NAME
-libpng \- Portable Network Graphics (PNG) Reference Library 1.2.1beta3
+libpng \- Portable Network Graphics (PNG) Reference Library 1.2.1beta4
 (private functions)
 .SH SYNOPSIS
 \fB#include <png.h>\fP
diff --git a/png.5 b/png.5
index 27bfb78e..2a8fe105 100644
--- a/png.5
+++ b/png.5
@@ -1,4 +1,4 @@
-.TH PNG 5 "October 27, 2001"
+.TH PNG 5 "November 7, 2001"
 .SH NAME
 png \- Portable Network Graphics (PNG) format
 .SH DESCRIPTION
diff --git a/png.c b/png.c
index 6037fada..6b10ff80 100644
--- a/png.c
+++ b/png.c
@@ -1,7 +1,7 @@
 
 /* png.c - location for general purpose libpng functions
  *
- * libpng version 1.2.1beta3 - October 27, 2001
+ * libpng version 1.2.1beta4 - November 7, 2001
  * Copyright (c) 1998-2001 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
@@ -13,14 +13,14 @@
 #include "png.h"
 
 /* Generate a compiler error if there is an old png.h in the search path. */
-typedef version_1_2_1beta3 Your_png_h_is_not_version_1_2_1beta3;
+typedef version_1_2_1beta4 Your_png_h_is_not_version_1_2_1beta4;
 
 /* Version information for C files.  This had better match the version
  * string defined in png.h.  */
 
 #ifdef PNG_USE_GLOBAL_ARRAYS
 /* png_libpng_ver was changed to a function in version 1.0.5c */
-const char png_libpng_ver[18] = "1.2.1beta3";
+const char png_libpng_ver[18] = "1.2.1beta4";
 
 /* png_sig was changed to a function in version 1.0.5c */
 /* Place to hold the signature string for a PNG file. */
@@ -212,14 +212,13 @@ png_create_info_struct(png_structp png_ptr)
    png_debug(1, "in png_create_info_struct\n");
    if(png_ptr == NULL) return (NULL);
 #ifdef PNG_USER_MEM_SUPPORTED
-   if ((info_ptr = (png_infop)png_create_struct_2(PNG_STRUCT_INFO,
-      png_ptr->malloc_fn, png_ptr->mem_ptr)) != NULL)
+   info_ptr = (png_infop)png_create_struct_2(PNG_STRUCT_INFO,
+      png_ptr->malloc_fn, png_ptr->mem_ptr);
 #else
-   if ((info_ptr = (png_infop)png_create_struct(PNG_STRUCT_INFO)) != NULL)
+   info_ptr = (png_infop)png_create_struct(PNG_STRUCT_INFO);
 #endif
-   {
+   if (info_ptr != NULL)
       png_info_init_3(&info_ptr, sizeof(png_info));
-   }
 
    return (info_ptr);
 }
@@ -646,7 +645,7 @@ png_charp PNGAPI
 png_get_copyright(png_structp png_ptr)
 {
    if (png_ptr != NULL || png_ptr == NULL)  /* silence compiler warning */
-   return ((png_charp) "\n libpng version 1.2.1beta3 - October 27, 2001\n\
+   return ((png_charp) "\n libpng version 1.2.1beta4 - November 7, 2001\n\
    Copyright (c) 1998-2001 Glenn Randers-Pehrson\n\
    Copyright (c) 1996, 1997 Andreas Dilger\n\
    Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.\n");
@@ -664,8 +663,8 @@ png_get_libpng_ver(png_structp png_ptr)
 {
    /* Version of *.c files used when building libpng */
    if(png_ptr != NULL) /* silence compiler warning about unused png_ptr */
-      return((png_charp) "1.2.1beta3");
-   return((png_charp) "1.2.1beta3");
+      return((png_charp) "1.2.1beta4");
+   return((png_charp) "1.2.1beta4");
 }
 
 png_charp PNGAPI
diff --git a/png.h b/png.h
index b65eeab8..86cb6264 100644
--- a/png.h
+++ b/png.h
@@ -1,7 +1,7 @@
 
 /* png.h - header file for PNG reference library
  *
- * libpng version 1.2.1beta3 - October 27, 2001
+ * libpng version 1.2.1beta4 - November 7, 2001
  * Copyright (c) 1998-2001 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
@@ -9,7 +9,7 @@
  * Authors and maintainers:
  *  libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat
  *  libpng versions 0.89c, June 1996, through 0.96, May 1997: Andreas Dilger
- *  libpng versions 0.97, January 1998, through 1.2.1beta3 - October 27, 2001: Glenn
+ *  libpng versions 0.97, January 1998, through 1.2.1beta4 - November 7, 2001: Glenn
  *  See also "Contributing Authors", below.
  *
  * Note about libpng version numbers:
@@ -78,7 +78,7 @@
  *    1.2.0beta3-5             3    10200  3.1.2.0beta3-5
  *    1.2.0rc1                 3    10200  3.1.2.0rc1
  *    1.2.0                    3    10200  3.1.2.0
- *    1.2.1beta1-3             3    10201  3.1.2.1beta1-3
+ *    1.2.1beta1-4             3    10201  3.1.2.1beta1-4
  *
  *    Henceforth the source version will match the shared-library major
  *    and minor numbers; the shared-library major version number will be
@@ -108,7 +108,7 @@
  * If you modify libpng you may insert additional notices immediately following
  * this sentence.
  *
- * libpng versions 1.0.7, July 1, 2000, through  1.2.1beta3, October 27, 2001, are
+ * libpng versions 1.0.7, July 1, 2000, through  1.2.1beta4, November 7, 2001, are
  * Copyright (c) 2000, 2001 Glenn Randers-Pehrson, and are
  * distributed according to the same disclaimer and license as libpng-1.0.6
  * with the following individuals added to the list of Contributing Authors
@@ -213,13 +213,13 @@
  * Y2K compliance in libpng:
  * =========================
  *
- *    October 27, 2001
+ *    November 7, 2001
  *
  *    Since the PNG Development group is an ad-hoc body, we can't make
  *    an official declaration.
  *
  *    This is your unofficial assurance that libpng from version 0.71 and
- *    upward through 1.2.1beta3 are Y2K compliant.  It is my belief that earlier
+ *    upward through 1.2.1beta4 are Y2K compliant.  It is my belief that earlier
  *    versions were also Y2K compliant.
  *
  *    Libpng only has three year fields.  One is a 2-byte unsigned integer
@@ -275,7 +275,7 @@
  */
 
 /* Version information for png.h - this should match the version in png.c */
-#define PNG_LIBPNG_VER_STRING "1.2.1beta3"
+#define PNG_LIBPNG_VER_STRING "1.2.1beta4"
 
 #define PNG_LIBPNG_VER_SONUM   3
 #define PNG_LIBPNG_VER_DLLNUM  %DLLNUM%
@@ -287,7 +287,7 @@
 /* This should match the numeric part of the final component of
  * PNG_LIBPNG_VER_STRING, omitting any leading zero: */
 
-#define PNG_LIBPNG_VER_BUILD  3
+#define PNG_LIBPNG_VER_BUILD  4
 
 #define PNG_LIBPNG_BUILD_ALPHA    1
 #define PNG_LIBPNG_BUILD_BETA     2
@@ -323,21 +323,39 @@ extern "C" {
  * which applications aren't expected to use directly.
  */
 
-#define int_p_NULL                NULL     /* (int *)NULL */
-#define png_bytep_NULL            NULL     /* (png_bytep)NULL */
-#define png_bytepp_NULL           NULL     /* (png_bytepp)NULL */
-#define png_doublep_NULL          NULL     /* (png_doublep)NULL */
-#define png_error_ptr_NULL        NULL     /* (png_error_ptr)NULL */
-#define png_flush_ptr_NULL        NULL     /* (png_flush_ptr)NULL */
-#define png_free_ptr_NULL         NULL     /* (png_free_ptr)NULL */
-#define png_infopp_NULL           NULL     /* (png_infopp)NULL */
-#define png_malloc_ptr_NULL       NULL     /* (png_malloc_ptr)NULL */
-#define png_read_status_ptr_NULL  NULL     /* (png_read_status_ptr)NULL */
-#define png_rw_ptr_NULL           NULL     /* (png_rw_ptr)NULL */
-#define png_structp_NULL          NULL     /* (png_structp)NULL */
-#define png_uint_16p_NULL         NULL     /* (png_uint_16p)NULL */
-#define png_voidp_NULL            NULL     /* (png_voidp)NULL */
-#define png_write_status_ptr_NULL NULL     /* (png_write_status_ptr)NULL */
+#ifdef PNG_TYPECAST_NULL
+#define int_p_NULL                (int *)NULL
+#define png_bytep_NULL            (png_bytep)NULL
+#define png_bytepp_NULL           (png_bytepp)NULL
+#define png_doublep_NULL          (png_doublep)NULL
+#define png_error_ptr_NULL        (png_error_ptr)NULL
+#define png_flush_ptr_NULL        (png_flush_ptr)NULL
+#define png_free_ptr_NULL         (png_free_ptr)NULL
+#define png_infopp_NULL           (png_infopp)NULL
+#define png_malloc_ptr_NULL       (png_malloc_ptr)NULL
+#define png_read_status_ptr_NULL  (png_read_status_ptr)NULL
+#define png_rw_ptr_NULL           (png_rw_ptr)NULL
+#define png_structp_NULL          (png_structp)NULL
+#define png_uint_16p_NULL         (png_uint_16p)NULL
+#define png_voidp_NULL            (png_voidp)NULL
+#define png_write_status_ptr_NULL (png_write_status_ptr)NULL
+#else
+#define int_p_NULL                NULL
+#define png_bytep_NULL            NULL
+#define png_bytepp_NULL           NULL
+#define png_doublep_NULL          NULL
+#define png_error_ptr_NULL        NULL
+#define png_flush_ptr_NULL        NULL
+#define png_free_ptr_NULL         NULL
+#define png_infopp_NULL           NULL
+#define png_malloc_ptr_NULL       NULL
+#define png_read_status_ptr_NULL  NULL
+#define png_rw_ptr_NULL           NULL
+#define png_structp_NULL          NULL
+#define png_uint_16p_NULL         NULL
+#define png_voidp_NULL            NULL
+#define png_write_status_ptr_NULL NULL
+#endif
 
 /* variables declared in png.c - only it needs to define PNG_NO_EXTERN */
 #if !defined(PNG_NO_EXTERN) || defined(PNG_ALWAYS_EXTERN)
@@ -1233,9 +1251,9 @@ struct png_struct_def
 
 
 /* This prevents a compiler error in png_get_copyright() in png.c if png.c
-   and png.h are both at version 1.2.1beta3
+   and png.h are both at version 1.2.1beta4
  */
-typedef png_structp version_1_2_1beta3;
+typedef png_structp version_1_2_1beta4;
 
 typedef png_struct FAR * FAR * png_structpp;
 
@@ -2352,7 +2370,7 @@ extern PNG_EXPORT(void,png_set_strip_error_numbers) PNGARG((png_structp
 /* Maintainer: Put new public prototypes here ^, in libpng.3, and project defs */
 
 #define PNG_HEADER_VERSION_STRING \
-   " libpng version 1.2.1beta3 - October 27, 2001 (header)\n"
+   " libpng version 1.2.1beta4 - November 7, 2001 (header)\n"
 
 #ifdef PNG_READ_COMPOSITE_NODIV_SUPPORTED
 /* With these routines we avoid an integer divide, which will be slower on
diff --git a/pngasmrd.h b/pngasmrd.h
index 9d3e7a2d..366ba34d 100644
--- a/pngasmrd.h
+++ b/pngasmrd.h
@@ -1,6 +1,6 @@
 /* pngasmrd.h - assembler version of utilities to read a PNG file
  *
- * libpng 1.2.1beta3 - October 27, 2001
+ * libpng 1.2.1beta4 - November 7, 2001
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 2001 Glenn Randers-Pehrson
  *
diff --git a/pngconf.h b/pngconf.h
index ba0a5aa8..a3284c38 100644
--- a/pngconf.h
+++ b/pngconf.h
@@ -1,6 +1,6 @@
 /* pngconf.h - machine configurable file for libpng
  *
- * libpng 1.2.1beta3 - October 27, 2001
+ * libpng 1.2.1beta4 - November 7, 2001
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1998-2001 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
@@ -202,6 +202,9 @@
 
 #ifdef _NO_PROTO
 #  define PNGARG(arglist) ()
+#  ifndef PNG_TYPECAST_NULL
+#     define PNG_TYPECAST_NULL
+#  endif
 #else
 #  define PNGARG(arglist) arglist
 #endif /* _NO_PROTO */
diff --git a/pngerror.c b/pngerror.c
index 72ea3626..952f1b8d 100644
--- a/pngerror.c
+++ b/pngerror.c
@@ -1,7 +1,7 @@
 
 /* pngerror.c - stub functions for i/o and memory allocation
  *
- * libpng 1.2.1beta3 - October 27, 2001
+ * libpng 1.2.1beta4 - November 7, 2001
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1998-2001 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
diff --git a/pnggccrd.c b/pnggccrd.c
index ed9d864b..7aed706f 100644
--- a/pnggccrd.c
+++ b/pnggccrd.c
@@ -6,7 +6,7 @@
  *     and http://www.intel.com/drg/pentiumII/appnotes/923/923.htm
  *     for Intel's performance analysis of the MMX vs. non-MMX code.
  *
- * libpng version 1.2.1beta3 - October 27, 2001
+ * libpng version 1.2.1beta4 - November 7, 2001
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1998-2001 Glenn Randers-Pehrson
  * Copyright (c) 1998, Intel Corporation
diff --git a/pngget.c b/pngget.c
index 9d6138fd..399e01f2 100644
--- a/pngget.c
+++ b/pngget.c
@@ -1,7 +1,7 @@
 
 /* pngget.c - retrieval of values from info struct
  *
- * libpng 1.2.1beta3 - October 27, 2001
+ * libpng 1.2.1beta4 - November 7, 2001
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1998-2001 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
diff --git a/pngmem.c b/pngmem.c
index 53cccdbf..15971dfd 100644
--- a/pngmem.c
+++ b/pngmem.c
@@ -1,7 +1,7 @@
 
 /* pngmem.c - stub functions for memory allocation
  *
- * libpng 1.2.1beta3 - October 27, 2001
+ * libpng 1.2.1beta4 - November 7, 2001
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1998-2001 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
@@ -51,7 +51,7 @@ png_create_struct_2(int type, png_malloc_ptr malloc_fn, png_voidp mem_ptr)
       png_struct dummy_struct;
       png_structp png_ptr = &dummy_struct;
       png_ptr->mem_ptr=mem_ptr;
-      struct_ptr = (*(malloc_fn))(png_ptr, size);
+      struct_ptr = (*(malloc_fn))(png_ptr, (png_uint_32)size);
    }
    else
 #endif /* PNG_USER_MEM_SUPPORTED */
@@ -311,17 +311,10 @@ png_create_struct_2(int type, png_malloc_ptr malloc_fn, png_voidp mem_ptr)
 #ifdef PNG_USER_MEM_SUPPORTED
    if(malloc_fn != NULL)
    {
-      if (mem_ptr != NULL)
-      {
-         png_struct dummy_struct;
-         png_structp png_ptr = &dummy_struct;
-         png_ptr->mem_ptr=mem_ptr;
-         struct_ptr = (*(malloc_fn))(png_ptr, size);
-      }
-      else
-      {
-         struct_ptr = (*(malloc_fn))(png_structp_NULL, size);
-      }
+      png_struct dummy_struct;
+      png_structp png_ptr = &dummy_struct;
+      png_ptr->mem_ptr=mem_ptr;
+      struct_ptr = (*(malloc_fn))(png_ptr, (png_uint_32)size);
       if (struct_ptr != NULL)
          png_memset(struct_ptr, 0, size);
       return (struct_ptr);
diff --git a/pngpread.c b/pngpread.c
index 5c97687e..b1a1d93d 100644
--- a/pngpread.c
+++ b/pngpread.c
@@ -1,7 +1,7 @@
 
 /* pngpread.c - read a png file in push mode
  *
- * libpng 1.2.1beta3 - October 27, 2001
+ * libpng 1.2.1beta4 - November 7, 2001
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1998-2001 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
diff --git a/pngread.c b/pngread.c
index 79ac8a0f..2ffd82bb 100644
--- a/pngread.c
+++ b/pngread.c
@@ -1,7 +1,7 @@
 
 /* pngread.c - read a PNG file
  *
- * libpng 1.2.1beta3 - October 27, 2001
+ * libpng 1.2.1beta4 - November 7, 2001
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1998-2001 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
@@ -105,7 +105,7 @@ png_create_read_struct_2(png_const_charp user_png_ver, png_voidp error_ptr,
              user_png_ver);
           png_warning(png_ptr, msg);
         }
-        sprintf(msg, "Application  is running with png.c from libpng-%.20s",
+        sprintf(msg, "Application  is  running with png.c from libpng-%.20s",
            png_libpng_ver);
         png_warning(png_ptr, msg);
 #endif
@@ -170,7 +170,7 @@ png_read_init_2(png_structp png_ptr, png_const_charp user_png_ver,
            user_png_ver);
         png_warning(png_ptr, msg);
       }
-      sprintf(msg, "Application  is running with png.c from libpng-%.20s",
+      sprintf(msg, "Application  is  running with png.c from libpng-%.20s",
          png_libpng_ver);
       png_warning(png_ptr, msg);
    }
@@ -767,7 +767,7 @@ png_read_row(png_structp png_ptr, png_bytep row, png_bytep dsp_row)
  * not called png_set_interlace_handling(), the display_row buffer will
  * be ignored, so pass NULL to it.
  *
- * [*] png_handle_alpha() does not exist yet, as of libpng version 1.2.1beta3
+ * [*] png_handle_alpha() does not exist yet, as of libpng version 1.2.1beta4
  */
 
 void PNGAPI
@@ -816,7 +816,7 @@ png_read_rows(png_structp png_ptr, png_bytepp row,
  * only call this function once.  If you desire to have an image for
  * each pass of a interlaced image, use png_read_rows() instead.
  *
- * [*] png_handle_alpha() does not exist yet, as of libpng version 1.2.1beta3
+ * [*] png_handle_alpha() does not exist yet, as of libpng version 1.2.1beta4
  */
 void PNGAPI
 png_read_image(png_structp png_ptr, png_bytepp image)
diff --git a/pngrio.c b/pngrio.c
index 8cb05d44..c91f87e6 100644
--- a/pngrio.c
+++ b/pngrio.c
@@ -1,7 +1,7 @@
 
 /* pngrio.c - functions for data input
  *
- * libpng 1.2.1beta3 - October 27, 2001
+ * libpng 1.2.1beta4 - November 7, 2001
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1998-2001 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
diff --git a/pngrtran.c b/pngrtran.c
index 2b57688d..40222388 100644
--- a/pngrtran.c
+++ b/pngrtran.c
@@ -1,7 +1,7 @@
 
 /* pngrtran.c - transforms the data in a row for PNG readers
  *
- * libpng 1.2.1beta3 - October 27, 2001
+ * libpng 1.2.1beta4 - November 7, 2001
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1998-2001 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
diff --git a/pngrutil.c b/pngrutil.c
index 5da8037b..634ac835 100644
--- a/pngrutil.c
+++ b/pngrutil.c
@@ -1,7 +1,7 @@
 
 /* pngrutil.c - utilities to read a PNG file
  *
- * libpng 1.2.1beta3 - October 27, 2001
+ * libpng 1.2.1beta4 - November 7, 2001
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1998-2001 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
diff --git a/pngset.c b/pngset.c
index c3a1c1a2..baffcca2 100644
--- a/pngset.c
+++ b/pngset.c
@@ -1,7 +1,7 @@
 
 /* pngset.c - storage of image information into info struct
  *
- * libpng 1.2.1beta3 - October 27, 2001
+ * libpng 1.2.1beta4 - November 7, 2001
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1998-2001 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
diff --git a/pngtest.c b/pngtest.c
index e89d912b..08ca1d1f 100644
--- a/pngtest.c
+++ b/pngtest.c
@@ -1,7 +1,7 @@
 
 /* pngtest.c - a simple test program to test libpng
  *
- * libpng 1.2.1beta3 - October 27, 2001
+ * libpng 1.2.1beta4 - November 7, 2001
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1998-2001 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
@@ -1512,4 +1512,4 @@ main(int argc, char *argv[])
 }
 
 /* Generate a compiler error if there is an old png.h in the search path. */
-typedef version_1_2_1beta3 your_png_h_is_not_version_1_2_1beta3;
+typedef version_1_2_1beta4 your_png_h_is_not_version_1_2_1beta4;
diff --git a/pngtrans.c b/pngtrans.c
index 871db41d..cc7bf191 100644
--- a/pngtrans.c
+++ b/pngtrans.c
@@ -1,7 +1,7 @@
 
 /* pngtrans.c - transforms the data in a row (used by both readers and writers)
  *
- * libpng 1.2.1beta3 - October 27, 2001
+ * libpng 1.2.1beta4 - November 7, 2001
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1998-2001 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
diff --git a/pngvcrd.c b/pngvcrd.c
index 6d27a3da..0213ee4c 100644
--- a/pngvcrd.c
+++ b/pngvcrd.c
@@ -2,7 +2,7 @@
  *
  * For Intel x86 CPU and Microsoft Visual C++ compiler
  *
- * libpng 1.2.1beta3 - October 27, 2001
+ * libpng 1.2.1beta4 - November 7, 2001
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1998-2001 Glenn Randers-Pehrson
  * Copyright (c) 1998, Intel Corporation
diff --git a/pngwio.c b/pngwio.c
index d648164a..dd96b407 100644
--- a/pngwio.c
+++ b/pngwio.c
@@ -1,7 +1,7 @@
 
 /* pngwio.c - functions for data output
  *
- * libpng 1.2.1beta3 - October 27, 2001
+ * libpng 1.2.1beta4 - November 7, 2001
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1998-2001 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
diff --git a/pngwrite.c b/pngwrite.c
index 9301fd82..d0331e37 100644
--- a/pngwrite.c
+++ b/pngwrite.c
@@ -1,7 +1,7 @@
 
 /* pngwrite.c - general routines to write a PNG file
  *
- * libpng 1.2.1beta3 - October 27, 2001
+ * libpng 1.2.1beta4 - November 7, 2001
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1998-2001 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
@@ -502,7 +502,7 @@ png_create_write_struct_2(png_const_charp user_png_ver, png_voidp error_ptr,
              user_png_ver);
           png_warning(png_ptr, msg);
         }
-        sprintf(msg, "Application  is running with png.c from libpng-%.20s",
+        sprintf(msg, "Application  is  running with png.c from libpng-%.20s",
            png_libpng_ver);
         png_warning(png_ptr, msg);
 #endif
@@ -556,7 +556,7 @@ png_write_init_2(png_structp png_ptr, png_const_charp user_png_ver,
            user_png_ver);
         png_warning(png_ptr, msg);
       }
-      sprintf(msg, "Application  is running with png.c from libpng-%.20s",
+      sprintf(msg, "Application  is  running with png.c from libpng-%.20s",
          png_libpng_ver);
       png_warning(png_ptr, msg);
    }
@@ -705,6 +705,11 @@ png_write_row(png_structp png_ptr, png_bytep row)
    /* initialize transformations and other stuff if first time */
    if (png_ptr->row_number == 0 && png_ptr->pass == 0)
    {
+   /* make sure we wrote the header info */
+   if (!(png_ptr->mode & PNG_WROTE_INFO_BEFORE_PLTE))
+      png_error(png_ptr,
+         "png_write_info was never called before png_write_row.");
+
    /* check for transforms that have been set but were defined out */
 #if !defined(PNG_WRITE_INVERT_SUPPORTED) && defined(PNG_READ_INVERT_SUPPORTED)
    if (png_ptr->transformations & PNG_INVERT_MONO)
diff --git a/pngwtran.c b/pngwtran.c
index 37790468..7791709e 100644
--- a/pngwtran.c
+++ b/pngwtran.c
@@ -1,7 +1,7 @@
 
 /* pngwtran.c - transforms the data in a row for PNG writers
  *
- * libpng 1.2.1beta3 - October 27, 2001
+ * libpng 1.2.1beta4 - November 7, 2001
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1998-2001 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
diff --git a/pngwutil.c b/pngwutil.c
index d4209331..a0cd1554 100644
--- a/pngwutil.c
+++ b/pngwutil.c
@@ -1,7 +1,7 @@
 
 /* pngwutil.c - utilities to write a PNG file
  *
- * libpng 1.2.1beta3 - October 27, 2001
+ * libpng 1.2.1beta4 - November 7, 2001
  * For conditions of distribution and use, see copyright notice in png.h
  * Copyright (c) 1998-2001 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
diff --git a/projects/msvc/README.txt b/projects/msvc/README.txt
index a2b3eb04..2ade89a8 100644
--- a/projects/msvc/README.txt
+++ b/projects/msvc/README.txt
@@ -1,5 +1,5 @@
 Microsoft Developer Studio Build File, Format Version 6.00 for
-libpng 1.2.1beta3 (October 27, 2001) and zlib
+libpng 1.2.1beta4 (November 7, 2001) and zlib
 
 Copyright (C) 2000 Simon-Pierre Cadieux
 For conditions of distribution and use, see copyright notice in png.h
diff --git a/projects/msvc/png32ms.def b/projects/msvc/png32ms.def
index 52a86439..0d3075c5 100644
--- a/projects/msvc/png32ms.def
+++ b/projects/msvc/png32ms.def
@@ -6,7 +6,7 @@ LIBRARY
 DESCRIPTION "PNG image compression library for Windows"
 
 EXPORTS
-;Version 1.2.1beta3
+;Version 1.2.1beta4
   png_build_grayscale_palette  @1
   png_check_sig        @2
   png_chunk_error      @3
diff --git a/projects/netware.txt b/projects/netware.txt
index de3cd1c3..f2fcddb7 100644
--- a/projects/netware.txt
+++ b/projects/netware.txt
@@ -1,6 +1,6 @@
 A set of project files is available for Netware.  Get
-libpng-1.2.1beta3-project-netware.zip from a libpng distribution
+libpng-1.2.1beta4-project-netware.zip from a libpng distribution
 site such as http://libpng.sourceforge.net
 
 Put the zip file in this directory (projects) and then run
-"unzip -a libpng-1.2.1beta3-project-netware.zip"
+"unzip -a libpng-1.2.1beta4-project-netware.zip"
diff --git a/projects/wince.txt b/projects/wince.txt
index ae14bd9c..5b05ac2b 100644
--- a/projects/wince.txt
+++ b/projects/wince.txt
@@ -1,6 +1,6 @@
 A set of project files is available for WinCE.  Get
-libpng-1.2.1beta3-project-wince.zip from a libpng distribution
+libpng-1.2.1beta4-project-wince.zip from a libpng distribution
 site such as http://libpng.sourceforge.net
 
 Put the zip file in this directory (projects) and then run
-"unzip -a libpng-1.2.1beta3-project-wince.zip"
+"unzip -a libpng-1.2.1beta4-project-wince.zip"
diff --git a/scripts/makefile.aix b/scripts/makefile.aix
index 553bee53..b5488566 100644
--- a/scripts/makefile.aix
+++ b/scripts/makefile.aix
@@ -18,7 +18,7 @@ RM = rm -f
 # read libpng.txt or png.h to see why PNGMAJ is 3.  You should not
 # have to change it.
 PNGMAJ = 3
-PNGMIN = 1.2.1beta3
+PNGMIN = 1.2.1beta4
 PNGVER = $(PNGMAJ).$(PNGMIN)
 
 prefix=/usr/local
diff --git a/scripts/makefile.beos b/scripts/makefile.beos
index 07aa69d1..07f07db4 100644
--- a/scripts/makefile.beos
+++ b/scripts/makefile.beos
@@ -13,7 +13,7 @@ ZLIBINC=/usr/local/include
 # read libpng.txt or png.h to see why PNGMAJ is 3.  You should not
 # have to change it.
 PNGMAJ = 3
-PNGMIN = 1.2.1beta3
+PNGMIN = 1.2.1beta4
 PNGVER = $(PNGMAJ).$(PNGMIN)
 
 ALIGN=
diff --git a/scripts/makefile.cygwin b/scripts/makefile.cygwin
index 17f27f02..63284032 100644
--- a/scripts/makefile.cygwin
+++ b/scripts/makefile.cygwin
@@ -39,7 +39,7 @@ CFLAGS=-I$(ZLIBINC) -Wall -O3 $(ALIGN) -funroll-loops \
 # have to change it.
 PNGMAJ = 3
 #PNGDLL = $3
-PNGMIN = 1.2.1beta3
+PNGMIN = 1.2.1beta4
 PNGMIN_BASE = 1.2.1
 PNGVER = $(PNGMAJ).$(PNGMIN)
 
diff --git a/scripts/makefile.darwin b/scripts/makefile.darwin
index 8b1a7cd1..e5a3ccf4 100644
--- a/scripts/makefile.darwin
+++ b/scripts/makefile.darwin
@@ -24,7 +24,7 @@ RANLIB=ranlib
 # read libpng.txt or png.h to see why PNGMAJ is 3.  You should not
 # have to change it.
 PNGMAJ = 3
-PNGMIN = 1.2.1beta3
+PNGMIN = 1.2.1beta4
 PNGVER = $(PNGMAJ).$(PNGMIN)
 
 INCPATH=$(prefix)/include
diff --git a/scripts/makefile.dec b/scripts/makefile.dec
index bdf22cb9..9f027e47 100644
--- a/scripts/makefile.dec
+++ b/scripts/makefile.dec
@@ -17,7 +17,7 @@ ZLIBINC=../zlib
 # read libpng.txt or png.h to see why PNGMAJ is 3.  You should not
 # have to change it.
 PNGMAJ = 3
-PNGMIN = 1.2.1beta3
+PNGMIN = 1.2.1beta4
 PNGVER = $(PNGMAJ).$(PNGMIN)
 
 CC=cc
diff --git a/scripts/makefile.gcmmx b/scripts/makefile.gcmmx
index 6a7d9cb5..dc8b3a54 100644
--- a/scripts/makefile.gcmmx
+++ b/scripts/makefile.gcmmx
@@ -55,7 +55,7 @@ RANLIB=ranlib
 # read libpng.txt or png.h to see why PNGMAJ is 3.  You should not
 # have to change it.
 PNGMAJ = 3
-PNGMIN = 1.2.1beta3
+PNGMIN = 1.2.1beta4
 PNGVER = $(PNGMAJ).$(PNGMIN)
 
 INCPATH=$(prefix)/include
diff --git a/scripts/makefile.hpgcc b/scripts/makefile.hpgcc
index 86f3a704..722b4e50 100644
--- a/scripts/makefile.hpgcc
+++ b/scripts/makefile.hpgcc
@@ -34,7 +34,7 @@ RANLIB=ranlib
 # read libpng.txt or png.h to see why PNGMAJ is 3.  You should not
 # have to change it.
 PNGMAJ = 3
-PNGMIN = 1.2.1beta3
+PNGMIN = 1.2.1beta4
 PNGVER = $(PNGMAJ).$(PNGMIN)
 
 INCPATH=$(prefix)/include
diff --git a/scripts/makefile.hpux b/scripts/makefile.hpux
index edc4a17e..2bb5bfa1 100644
--- a/scripts/makefile.hpux
+++ b/scripts/makefile.hpux
@@ -19,7 +19,7 @@ RANLIB=ranlib
 # read libpng.txt or png.h to see why PNGMAJ is 3.  You should not
 # have to change it.
 PNGMAJ = 3
-PNGMIN = 1.2.1beta3
+PNGMIN = 1.2.1beta4
 PNGVER = $(PNGMAJ).$(PNGMIN)
 
 # where make install puts libpng.a and png.h
diff --git a/scripts/makefile.linux b/scripts/makefile.linux
index d60a1ee0..f907f5de 100644
--- a/scripts/makefile.linux
+++ b/scripts/makefile.linux
@@ -34,7 +34,7 @@ RANLIB=ranlib
 # read libpng.txt or png.h to see why PNGMAJ is 3.  You should not
 # have to change it.
 PNGMAJ = 3
-PNGMIN = 1.2.1beta3
+PNGMIN = 1.2.1beta4
 PNGVER = $(PNGMAJ).$(PNGMIN)
 
 INCPATH=$(prefix)/include
diff --git a/scripts/makefile.macosx b/scripts/makefile.macosx
index 44d8cfd7..81b4c261 100644
--- a/scripts/makefile.macosx
+++ b/scripts/makefile.macosx
@@ -19,7 +19,7 @@ LDFLAGS=-L. -L$(ZLIBLIB) -lpng -lz
 LDSHARED=cc -lz -dynamiclib -compatibility_version $(VER) -current_version $(VER)
 
 PNGMAJ = 3
-PNGMIN = 1.2.1beta3
+PNGMIN = 1.2.1beta4
 VER = $(PNGMAJ).$(PNGMIN)
 SHAREDLIB=libpng
 SHAREDLIB_POSTFIX=dylib
diff --git a/scripts/makefile.netbsd b/scripts/makefile.netbsd
index 37cdc9fb..1b5fc7a2 100644
--- a/scripts/makefile.netbsd
+++ b/scripts/makefile.netbsd
@@ -11,7 +11,7 @@ INCSDIR=${LOCALBASE}/include
 
 LIB=png
 SHLIB_MAJOR= 3
-SHLIB_MINOR= 1.2.1beta3
+SHLIB_MINOR= 1.2.1beta4
 SRCS=	pnggccrd.c png.c pngset.c pngget.c pngrutil.c pngtrans.c pngwutil.c \
 	pngread.c pngrio.c pngwio.c pngwrite.c pngrtran.c \
 	pngwtran.c pngmem.c pngerror.c pngpread.c
diff --git a/scripts/makefile.sco b/scripts/makefile.sco
index 82aedf85..81f64e1c 100644
--- a/scripts/makefile.sco
+++ b/scripts/makefile.sco
@@ -25,7 +25,7 @@ RANLIB=echo
 # read libpng.txt or png.h to see why PNGMAJ is 3.  You should not
 # have to change it.
 PNGMAJ = 3
-PNGMIN = 1.2.1beta3
+PNGMIN = 1.2.1beta4
 PNGVER = $(PNGMAJ).$(PNGMIN)
 
 INCPATH=$(prefix)/include
diff --git a/scripts/makefile.sggcc b/scripts/makefile.sggcc
index f0d97d51..d5d4f1f0 100644
--- a/scripts/makefile.sggcc
+++ b/scripts/makefile.sggcc
@@ -22,7 +22,7 @@ CFLAGS=$(ABI) -I$(ZLIBINC) -O2 $(WARNMORE) -fPIC -mabi=n32
 LDFLAGS=$(ABI) -L. -L$(ZLIBLIB) -lpng -lz -lm
 LDSHARED=CC $(ABI) -shared
 
-VER=1.2.1beta3
+VER=1.2.1beta4
 # See "man dso" for info about shared objects
 SONUM=3
 LIBS=libpng.so.$(SONUM).$(VER)
diff --git a/scripts/makefile.sgi b/scripts/makefile.sgi
index 18fdaaa1..565bbf45 100644
--- a/scripts/makefile.sgi
+++ b/scripts/makefile.sgi
@@ -27,7 +27,7 @@ CFLAGS=$(ABI) -I$(ZLIBINC) -O $(WARNMORE) -DPNG_USE_PNGGCCRD -DPNG_NO_ASSEMBLER_
 LDFLAGS=$(ABI) -L. -L$(ZLIBLIB) -lpng -lz -lm
 LDSHARED=cc $(ABI) -shared
 
-VER=1.2.1beta3
+VER=1.2.1beta4
 # See "man dso" for info about shared objects
 SONUM=3
 SHAREDLIB=libpng.so
diff --git a/scripts/makefile.so9 b/scripts/makefile.so9
index 5e2e3776..9a635ff5 100644
--- a/scripts/makefile.so9
+++ b/scripts/makefile.so9
@@ -35,7 +35,7 @@ RANLIB=echo
 # read libpng.txt or png.h to see why PNGMAJ is 3.  You should not
 # have to change it.
 PNGMAJ = 3
-PNGMIN = 1.2.1beta3
+PNGMIN = 1.2.1beta4
 PNGVER = $(PNGMAJ).$(PNGMIN)
 
 INCPATH=$(prefix)/include
diff --git a/scripts/makefile.solaris b/scripts/makefile.solaris
index 402ffea3..6a0da519 100644
--- a/scripts/makefile.solaris
+++ b/scripts/makefile.solaris
@@ -31,7 +31,7 @@ RANLIB=echo
 # read libpng.txt or png.h to see why PNGMAJ is 3.  You should not
 # have to change it.
 PNGMAJ = 3
-PNGMIN = 1.2.1beta3
+PNGMIN = 1.2.1beta4
 PNGVER = $(PNGMAJ).$(PNGMIN)
 
 INCPATH=$(prefix)/include
diff --git a/scripts/pngdef.pas b/scripts/pngdef.pas
index 1c06a0aa..d0ce78f1 100644
--- a/scripts/pngdef.pas
+++ b/scripts/pngdef.pas
@@ -7,7 +7,7 @@ unit pngdef;
 interface
 
 const
-  PNG_LIBPNG_VER_STRING = '1.2.1beta3';
+  PNG_LIBPNG_VER_STRING = '1.2.1beta4';
   PNG_LIBPNG_VER        =  10201;
 
 type
diff --git a/scripts/pngos2.def b/scripts/pngos2.def
index 08feedf7..166d06c2 100644
--- a/scripts/pngos2.def
+++ b/scripts/pngos2.def
@@ -2,7 +2,7 @@
 ; PNG.LIB module definition file for OS/2
 ;----------------------------------------
 
-; Version 1.2.1beta3
+; Version 1.2.1beta4
 
 LIBRARY		PNG
 DESCRIPTION	"PNG image compression library for OS/2"