diff --git a/ANNOUNCE b/ANNOUNCE
index 314322ca..1e226121 100644
--- a/ANNOUNCE
+++ b/ANNOUNCE
@@ -1,5 +1,5 @@
 
-Libpng 1.2.51beta01 - December 10, 2012
+Libpng 1.2.51beta01 - January 1, 2013
 
 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.
@@ -42,7 +42,7 @@ Other information:
 
 Changes since the last public release (1.2.50):
 
-version 1.2.51beta01 [December 10, 2012]
+version 1.2.51beta01 [January 1, 2013]
   Ignore, with a warning, out-of-range value of num_trans in png_set_tRNS().
 
 (subscription required; visit
diff --git a/CHANGES b/CHANGES
index 6955ada6..9c5ce6a0 100644
--- a/CHANGES
+++ b/CHANGES
@@ -2777,7 +2777,7 @@ version 1.0.59 and 1.2.49 [March 29, 2012]
 version 1.0.60 and 1.2.50 [July 9, 2012]
   Changed "a+w" to "u+w" in Makefile.in to fix CVE-2012-3386.
 
-version 1.2.51beta01 [December 10, 2012]
+version 1.2.51beta01 [January 1, 2013]
   Rebuilt the configure scripts with autoconf-2.69
   Ignore, with a warning, out-of-range value of num_trans in png_set_tRNS().
 
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 00d9f7e4..0b53071f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -22,7 +22,7 @@ enable_testing()
 
 set(PNGLIB_MAJOR 1)
 set(PNGLIB_MINOR 2)
-set(PNGLIB_RELEASE 50)
+set(PNGLIB_RELEASE 51)
 set(PNGLIB_NAME libpng${PNGLIB_MAJOR}${PNGLIB_MINOR})
 set(PNGLIB_VERSION ${PNGLIB_MAJOR}.${PNGLIB_MINOR}.${PNGLIB_RELEASE})
 
@@ -215,7 +215,7 @@ configure_file(${CMAKE_CURRENT_SOURCE_DIR}/scripts/libpng-config.in
 # SET UP LINKS
 if(PNG_SHARED)
   set_target_properties(${PNG_LIB_NAME} PROPERTIES
-#   VERSION 0.${PNGLIB_RELEASE}.1.2.50
+#   VERSION 0.${PNGLIB_RELEASE}.1.2.51beta01
     VERSION 0.${PNGLIB_RELEASE}.0
     SOVERSION 0
     CLEAN_DIRECT_OUTPUT 1)
diff --git a/INSTALL b/INSTALL
index f18fa54b..ad0f8da8 100644
--- a/INSTALL
+++ b/INSTALL
@@ -1,5 +1,5 @@
 
-Installing libpng version 1.2.50 - July 10, 2012
+Installing libpng version 1.2.51beta01 - January 1, 2013
 
 On Unix/Linux and similar systems, you can simply type
 
@@ -46,7 +46,7 @@ to have access to the 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-1.2.50" or "libpng12" and "zlib-1.2.3"
+might be called "libpng-1.2.51beta01" or "libpng12" and "zlib-1.2.3"
 or "zlib123") so that you have directories called "zlib" and "libpng".
 
 Your directory structure should look like this:
diff --git a/KNOWNBUG b/KNOWNBUG
index 0c7ba486..5658b9cd 100644
--- a/KNOWNBUG
+++ b/KNOWNBUG
@@ -1,5 +1,5 @@
 
-Known bugs in libpng version 1.2.50
+Known bugs in libpng version 1.2.51beta01
 
 1. February 23, 2006: The custom makefiles don't build libpng with -lz.
 
diff --git a/LICENSE b/LICENSE
index a684fe5a..8500123e 100644
--- a/LICENSE
+++ b/LICENSE
@@ -10,7 +10,7 @@ this sentence.
 
 This code is released under the libpng license.
 
-libpng versions 1.2.6, August 15, 2004, through 1.2.50, July 10, 2012, are
+libpng versions 1.2.6, August 15, 2004, through 1.2.51beta01, January 1, 2013, are
 Copyright (c) 2004, 2006-2009 Glenn Randers-Pehrson, and are
 distributed according to the same disclaimer and license as libpng-1.2.5
 with the following individual added to the list of Contributing Authors
@@ -108,4 +108,4 @@ certification mark of the Open Source Initiative.
 
 Glenn Randers-Pehrson
 glennrp at users.sourceforge.net
-July 10, 2012
+January 1, 2013
diff --git a/Makefile.am b/Makefile.am
index 55808486..95815664 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -89,7 +89,7 @@ EXTRA_DIST= \
 	${srcdir}/contrib/pngsuite/* \
 	${srcdir}/contrib/visupng/* \
 	$(TESTS) \
-	example.c libpng-1.2.50.txt pnggccrd.c pngvcrd.c
+	example.c libpng-1.2.51beta01.txt pnggccrd.c pngvcrd.c
 
 CLEANFILES= pngout.png libpng12.pc libpng12-config libpng.vers \
 libpng.sym
diff --git a/Makefile.in b/Makefile.in
index ba8f39ec..dd50c3a5 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -354,7 +354,7 @@ EXTRA_DIST = \
 	${srcdir}/contrib/pngsuite/* \
 	${srcdir}/contrib/visupng/* \
 	$(TESTS) \
-	example.c libpng-1.2.50.txt pnggccrd.c pngvcrd.c
+	example.c libpng-1.2.51beta01.txt pnggccrd.c pngvcrd.c
 
 CLEANFILES = pngout.png libpng12.pc libpng12-config libpng.vers \
 libpng.sym
diff --git a/README b/README
index 0b4e6ae4..60bbf479 100644
--- a/README
+++ b/README
@@ -1,4 +1,4 @@
-README for libpng version 1.2.50 - July 10, 2012 (shared library 12.0)
+README for libpng version 1.2.51beta01 - January 1, 2013 (shared library 12.0)
 See the note about version numbers near the top of png.h
 
 See INSTALL for instructions on how to install libpng.
@@ -199,11 +199,11 @@ Files in this distribution:
        makefile.std     =>  Generic UNIX makefile (cc, creates static
                             libpng.a)
        makefile.elf     =>  Linux/ELF gcc makefile symbol versioning,
-                            creates libpng12.so.0.1.2.50)
+                            creates libpng12.so.0.1.2.51beta01)
        makefile.linux   =>  Linux/ELF makefile (gcc, creates
-                            libpng12.so.0.1.2.50)
+                            libpng12.so.0.1.2.51beta01)
        makefile.gcmmx   =>  Linux/ELF makefile (gcc, creates
-                            libpng12.so.0.1.2.50, previously
+                            libpng12.so.0.1.2.51beta01, previously
                             used assembler code tuned for Intel MMX
                             platform)
        makefile.gcc     =>  Generic makefile (gcc, creates static
@@ -228,12 +228,12 @@ Files in this distribution:
        makefile.openbsd =>  OpenBSD makefile
        makefile.sgi     =>  Silicon Graphics IRIX (cc, creates static lib)
        makefile.sggcc   =>  Silicon Graphics
-                            (gcc, creates libpng12.so.0.1.2.50)
+                            (gcc, creates libpng12.so.0.1.2.51beta01)
        makefile.sunos   =>  Sun makefile
        makefile.solaris =>  Solaris 2.X makefile
-                            (gcc, creates libpng12.so.0.1.2.50)
+                            (gcc, creates libpng12.so.0.1.2.51beta01)
        makefile.so9     =>  Solaris 9 makefile
-                            (gcc, creates libpng12.so.0.1.2.50)
+                            (gcc, creates libpng12.so.0.1.2.51beta01)
        makefile.32sunu  =>  Sun Ultra 32-bit makefile
        makefile.64sunu  =>  Sun Ultra 64-bit makefile
        makefile.sco     =>  For SCO OSr5  ELF and Unixware 7 with Native cc
diff --git a/Y2KINFO b/Y2KINFO
index fd369967..434723eb 100644
--- a/Y2KINFO
+++ b/Y2KINFO
@@ -1,13 +1,13 @@
    Y2K compliance in libpng:
    =========================
 
-      July 10, 2012
+      January 1, 2013
 
       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 1.2.50 are Y2K compliant.  It is my belief that earlier
+      upward through 1.2.51beta01 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 3f91cbe4..200e08f8 100755
--- a/configure
+++ b/configure
@@ -1,6 +1,6 @@
 #! /bin/sh
 # Guess values for system-dependent variables and create Makefiles.
-# Generated by GNU Autoconf 2.65 for libpng 1.2.50.
+# Generated by GNU Autoconf 2.65 for libpng 1.2.51beta01.
 #
 # Report bugs to <png-mng-implement@lists.sourceforge.net>.
 #
@@ -701,8 +701,8 @@ MAKEFLAGS=
 # Identity of this package.
 PACKAGE_NAME='libpng'
 PACKAGE_TARNAME='libpng'
-PACKAGE_VERSION='1.2.50'
-PACKAGE_STRING='libpng 1.2.50'
+PACKAGE_VERSION='1.2.51beta01'
+PACKAGE_STRING='libpng 1.2.51beta01'
 PACKAGE_BUGREPORT='png-mng-implement@lists.sourceforge.net'
 PACKAGE_URL=''
 
@@ -1435,7 +1435,7 @@ if test "$ac_init_help" = "long"; then
   # Omit some internal or obsolete options to make the list less imposing.
   # This message is too long to be a string in the A/UX 3.1 sh.
   cat <<_ACEOF
-\`configure' configures libpng 1.2.50 to adapt to many kinds of systems.
+\`configure' configures libpng 1.2.51beta01 to adapt to many kinds of systems.
 
 Usage: $0 [OPTION]... [VAR=VALUE]...
 
@@ -1505,7 +1505,7 @@ fi
 
 if test -n "$ac_init_help"; then
   case $ac_init_help in
-     short | recursive ) echo "Configuration of libpng 1.2.50:";;
+     short | recursive ) echo "Configuration of libpng 1.2.51beta01:";;
    esac
   cat <<\_ACEOF
 
@@ -1612,7 +1612,7 @@ fi
 test -n "$ac_init_help" && exit $ac_status
 if $ac_init_version; then
   cat <<\_ACEOF
-libpng configure 1.2.50
+libpng configure 1.2.51beta01
 generated by GNU Autoconf 2.65
 
 Copyright (C) 2009 Free Software Foundation, Inc.
@@ -2037,7 +2037,7 @@ cat >config.log <<_ACEOF
 This file contains any messages produced by compilers while
 running configure, to aid debugging if configure makes a mistake.
 
-It was created by libpng $as_me 1.2.50, which was
+It was created by libpng $as_me 1.2.51beta01, which was
 generated by GNU Autoconf 2.65.  Invocation command line was
 
   $ $0 $@
@@ -2845,7 +2845,7 @@ fi
 
 # Define the identity of the package.
  PACKAGE='libpng'
- VERSION='1.2.50'
+ VERSION='1.2.51beta01'
 
 
 cat >>confdefs.h <<_ACEOF
@@ -2909,10 +2909,10 @@ fi
 
 
 
-PNGLIB_VERSION=1.2.50
+PNGLIB_VERSION=1.2.51beta01
 PNGLIB_MAJOR=1
 PNGLIB_MINOR=2
-PNGLIB_RELEASE=50
+PNGLIB_RELEASE=51
 
 
 
@@ -12079,7 +12079,7 @@ cat >>$CONFIG_STATUS <<\_ACEOF || ac_write_fail=1
 # report actual input values of CONFIG_FILES etc. instead of their
 # values after options handling.
 ac_log="
-This file was extended by libpng $as_me 1.2.50, which was
+This file was extended by libpng $as_me 1.2.51beta01, which was
 generated by GNU Autoconf 2.65.  Invocation command line was
 
   CONFIG_FILES    = $CONFIG_FILES
@@ -12145,7 +12145,7 @@ _ACEOF
 cat >>$CONFIG_STATUS <<_ACEOF || ac_write_fail=1
 ac_cs_config="`$as_echo "$ac_configure_args" | sed 's/^ //; s/[\\""\`\$]/\\\\&/g'`"
 ac_cs_version="\\
-libpng config.status 1.2.50
+libpng config.status 1.2.51beta01
 configured by $0, generated by GNU Autoconf 2.65,
   with options \\"\$ac_cs_config\\"
 
diff --git a/configure.ac b/configure.ac
index 057dca30..4ac51775 100644
--- a/configure.ac
+++ b/configure.ac
@@ -18,15 +18,15 @@ AC_PREREQ(2.59)
 
 dnl Version number stuff here:
 
-AC_INIT([libpng], [1.2.50], [png-mng-implement@lists.sourceforge.net])
+AC_INIT([libpng], [1.2.51beta01], [png-mng-implement@lists.sourceforge.net])
 AM_INIT_AUTOMAKE
 dnl stop configure from automagically running automake
 AM_MAINTAINER_MODE
 
-PNGLIB_VERSION=1.2.50
+PNGLIB_VERSION=1.2.51beta01
 PNGLIB_MAJOR=1
 PNGLIB_MINOR=2
-PNGLIB_RELEASE=50
+PNGLIB_RELEASE=51
 
 dnl End of version number stuff
 
diff --git a/contrib/pngminim/encoder/README b/contrib/pngminim/encoder/README
index 2285544f..76a6d79b 100644
--- a/contrib/pngminim/encoder/README
+++ b/contrib/pngminim/encoder/README
@@ -1,9 +1,9 @@
 This demonstrates the use of PNG_USER_CONFIG and pngusr.h
 
-To build a minimal write-only decoder with embedded libpng and zlib, run
+To build a minimal write-only encoder with embedded libpng and zlib, run
 
     gather.sh  # to collect needed files from pngminus, libpng, and zlib
     make
  
 If you prefer to use the shared libraries, go to contrib/pngminus
-and build the pnm2png application there. 
+and build the pnm2png application there.
diff --git a/libpng-1.2.50.txt b/libpng-1.2.51beta01.txt
similarity index 99%
rename from libpng-1.2.50.txt
rename to libpng-1.2.51beta01.txt
index 6f1b0899..36b3b06e 100644
--- a/libpng-1.2.50.txt
+++ b/libpng-1.2.51beta01.txt
@@ -1,6 +1,6 @@
 libpng.txt - A description on how to use and modify libpng
 
- libpng version 1.2.50 - July 10, 2012
+ libpng version 1.2.51beta01 - January 1, 2013
  Updated and distributed by Glenn Randers-Pehrson
  <glennrp at users.sourceforge.net>
  Copyright (c) 1998-2009 Glenn Randers-Pehrson
@@ -11,7 +11,7 @@ libpng.txt - A description on how to use and modify libpng
 
  Based on:
 
- libpng versions 0.97, January 1998, through 1.2.50 - July 10, 2012
+ libpng versions 0.97, January 1998, through 1.2.51beta01 - January 1, 2013
  Updated and distributed by Glenn Randers-Pehrson
  Copyright (c) 1998-2009 Glenn Randers-Pehrson
 
@@ -878,7 +878,7 @@ things.
 As of libpng version 1.2.9, png_set_expand_gray_1_2_4_to_8() was
 added.  It expands the sample depth without changing tRNS to alpha.
 
-As of libpng version 1.2.50, not all possible expansions are supported.
+As of libpng version 1.2.51beta01, not all possible expansions are supported.
 
 In the following table, the 01 means grayscale with depth<8, 31 means
 indexed with depth<8, other numerals represent the color type, "T" means
@@ -3179,13 +3179,13 @@ Other rules can be inferred by inspecting the libpng source.
 
 XIII. Y2K Compliance in libpng
 
-July 10, 2012
+January 1, 2013
 
 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 1.2.50 are Y2K compliant.  It is my belief that earlier
+upward through 1.2.51beta01 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/libpng.3 b/libpng.3
index 0724fb5a..1de47a42 100644
--- a/libpng.3
+++ b/libpng.3
@@ -1,6 +1,6 @@
-.TH LIBPNG 3 "July 10, 2012"
+.TH LIBPNG 3 "January 1, 2013"
 .SH NAME
-libpng \- Portable Network Graphics (PNG) Reference Library 1.2.50
+libpng \- Portable Network Graphics (PNG) Reference Library 1.2.51beta01
 .SH SYNOPSIS
 \fI\fB
 
@@ -821,7 +821,7 @@ 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 1.2.50 - July 10, 2012
+ libpng version 1.2.51beta01 - January 1, 2013
  Updated and distributed by Glenn Randers-Pehrson
  <glennrp at users.sourceforge.net>
  Copyright (c) 1998-2009 Glenn Randers-Pehrson
@@ -832,7 +832,7 @@ libpng.txt - A description on how to use and modify libpng
 
  Based on:
 
- libpng versions 0.97, January 1998, through 1.2.50 - July 10, 2012
+ libpng versions 0.97, January 1998, through 1.2.51beta01 - January 1, 2013
  Updated and distributed by Glenn Randers-Pehrson
  Copyright (c) 1998-2009 Glenn Randers-Pehrson
 
@@ -1699,7 +1699,7 @@ things.
 As of libpng version 1.2.9, png_set_expand_gray_1_2_4_to_8() was
 added.  It expands the sample depth without changing tRNS to alpha.
 
-As of libpng version 1.2.50, not all possible expansions are supported.
+As of libpng version 1.2.51beta01, not all possible expansions are supported.
 
 In the following table, the 01 means grayscale with depth<8, 31 means
 indexed with depth<8, other numerals represent the color type, "T" means
@@ -4000,13 +4000,13 @@ Other rules can be inferred by inspecting the libpng source.
 
 .SH XIII. Y2K Compliance in libpng
 
-July 10, 2012
+January 1, 2013
 
 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 1.2.50 are Y2K compliant.  It is my belief that earlier
+upward through 1.2.51beta01 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
@@ -4327,6 +4327,9 @@ the first widely used release:
  1.2.49rc01          13    10249  12.so.0.49[.0]
  1.0.59              10    10059  10.so.0.59[.0]
  1.2.49              13    10249  12.so.0.49[.0]
+ 1.2.50              13    10250  12.so.0.50[.0]
+ 1.0.60              10    10060  10.so.0.60[.0]
+ 1.2.51beta01        13    10251  12.so.0.51[.0]
 
 Henceforth the source version will match the shared-library minor
 and patch numbers; the shared-library major version number will be
@@ -4382,7 +4385,7 @@ possible without all of you.
 
 Thanks to Frank J. T. Wojcik for helping with the documentation.
 
-Libpng version 1.2.50 - July 10, 2012:
+Libpng version 1.2.51beta01 - January 1, 2013:
 Initially created in 1995 by Guy Eric Schalnat, then of Group 42, Inc.
 Currently maintained by Glenn Randers-Pehrson (glennrp at users.sourceforge.net).
 
@@ -4405,7 +4408,7 @@ this sentence.
 
 This code is released under the libpng license.
 
-libpng versions 1.2.6, August 15, 2004, through 1.2.50, July 10, 2012, are
+libpng versions 1.2.6, August 15, 2004, through 1.2.51beta01, January 1, 2013, are
 Copyright (c) 2004,2006-2008 Glenn Randers-Pehrson, and are
 distributed according to the same disclaimer and license as libpng-1.2.5
 with the following individual added to the list of Contributing Authors
@@ -4504,7 +4507,7 @@ certification mark of the Open Source Initiative.
 
 Glenn Randers-Pehrson
 glennrp at users.sourceforge.net
-July 10, 2012
+January 1, 2013
 
 .\" end of man page
 
diff --git a/libpngpf.3 b/libpngpf.3
index 9b921e6c..abdef005 100644
--- a/libpngpf.3
+++ b/libpngpf.3
@@ -1,6 +1,6 @@
-.TH LIBPNGPF 3 "July 10, 2012"
+.TH LIBPNGPF 3 "January 1, 2013"
 .SH NAME
-libpng \- Portable Network Graphics (PNG) Reference Library 1.2.50
+libpng \- Portable Network Graphics (PNG) Reference Library 1.2.51beta01
 (private functions)
 .SH SYNOPSIS
 \fB#include <png.h>\fP
diff --git a/png.5 b/png.5
index 23bbef97..c7c3fca5 100644
--- a/png.5
+++ b/png.5
@@ -1,4 +1,4 @@
-.TH PNG 5 "July 10, 2012"
+.TH PNG 5 "January 1, 2013"
 .SH NAME
 png \- Portable Network Graphics (PNG) format
 .SH DESCRIPTION
diff --git a/projects/wince.txt b/projects/wince.txt
index a058a191..8665523f 100644
--- a/projects/wince.txt
+++ b/projects/wince.txt
@@ -1,6 +1,6 @@
 A set of project files is available for WinCE.  Get
-libpng-1.2.50-project-wince.zip from a libpng distribution
+libpng-1.2.51beta01-project-wince.zip from a libpng distribution
 site such as http://libpng.sourceforge.net/index.html
 
 Put the zip file in this directory (projects) and then run
-"unzip -a libpng-1.2.50-project-wince.zip"
+"unzip -a libpng-1.2.51beta01-project-wince.zip"
diff --git a/projects/xcode/libpng.xcodeproj/project.pbxproj b/projects/xcode/libpng.xcodeproj/project.pbxproj
index 35f9ffe7..0cb83881 100644
--- a/projects/xcode/libpng.xcodeproj/project.pbxproj
+++ b/projects/xcode/libpng.xcodeproj/project.pbxproj
@@ -222,7 +222,7 @@
 				COPY_PHASE_STRIP = NO;
 				DYLIB_COMPATIBILITY_VERSION = 3;
 				DYLIB_CURRENT_VERSION = 3;
-				FRAMEWORK_VERSION = 1.2.50;
+				FRAMEWORK_VERSION = 1.2.51beta01;
 				GCC_PRECOMPILE_PREFIX_HEADER = NO;
 				GCC_PREFIX_HEADER = "";
 				INFOPLIST_FILE = Info.plist;
@@ -240,7 +240,7 @@
 			buildSettings = {
 				DYLIB_COMPATIBILITY_VERSION = 3;
 				DYLIB_CURRENT_VERSION = 3;
-				FRAMEWORK_VERSION = 1.2.50;
+				FRAMEWORK_VERSION = 1.2.51beta01;
 				GCC_PRECOMPILE_PREFIX_HEADER = NO;
 				GCC_PREFIX_HEADER = "";
 				INFOPLIST_FILE = Info.plist;
diff --git a/scripts/README.txt b/scripts/README.txt
index 3b6bb3ae..73ba0d40 100644
--- a/scripts/README.txt
+++ b/scripts/README.txt
@@ -1,8 +1,8 @@
 
-Makefiles for  libpng version 1.2.50 - July 10, 2012
+Makefiles for  libpng version 1.2.51beta01 - January 1, 2013
 
  makefile.linux    =>  Linux/ELF makefile
-                       (gcc, creates libpng12.so.0.1.2.50)
+                       (gcc, creates libpng12.so.0.1.2.51beta01)
  makefile.gcc      =>  Generic makefile (gcc, creates static libpng.a)
  makefile.knr      =>  Archaic UNIX Makefile that converts files with
                        ansi2knr (Requires ansi2knr.c from
@@ -20,7 +20,7 @@ Makefiles for  libpng version 1.2.50 - July 10, 2012
  makefile.dec      =>  DEC Alpha UNIX makefile
  makefile.dj2      =>  DJGPP 2 makefile
  makefile.elf      =>  Linux/ELF makefile symbol versioning,
-                       gcc, creates libpng12.so.0.1.2.50)
+                       gcc, creates libpng12.so.0.1.2.51beta01)
  makefile.freebsd  =>  FreeBSD makefile
  makefile.gcc      =>  Generic gcc makefile
  makefile.gccmmx   =>  Generic gcc makefile previously using MMX code
@@ -38,14 +38,14 @@ Makefiles for  libpng version 1.2.50 - July 10, 2012
  makefile.os2      =>  OS/2 Makefile (gcc and emx, requires pngos2.def)
  makefile.sco      =>  For SCO OSr5  ELF and Unixware 7 with Native cc
  makefile.sggcc    =>  Silicon Graphics (gcc,
-                       creates libpng12.so.0.1.2.50)
+                       creates libpng12.so.0.1.2.51beta01)
  makefile.sgi      =>  Silicon Graphics IRIX makefile (cc, creates static lib)
  makefile.solaris  =>  Solaris 2.X makefile (gcc,
-                       creates libpng12.so.0.1.2.50)
+                       creates libpng12.so.0.1.2.51beta01)
  makefile.solaris-x86  =>  Solaris 2.X makefile (gcc, no MMX code,
-                       creates libpng12.so.0.1.2.50)
+                       creates libpng12.so.0.1.2.51beta01)
  makefile.so9      =>  Solaris 9 makefile (gcc,
-                       creates libpng12.so.0.1.2.50)
+                       creates libpng12.so.0.1.2.51beta01)
  makefile.std      =>  Generic UNIX makefile (cc, creates static libpng.a)
  makefile.sunos    =>  Sun makefile
  makefile.32sunu   =>  Sun Ultra 32-bit makefile
diff --git a/scripts/libpng-config-head.in b/scripts/libpng-config-head.in
index 229dedc7..e2020a4f 100755
--- a/scripts/libpng-config-head.in
+++ b/scripts/libpng-config-head.in
@@ -11,7 +11,7 @@
 
 # Modeled after libxml-config.
 
-version=1.2.50
+version=1.2.51beta01
 prefix=""
 libdir=""
 libs=""
diff --git a/scripts/libpng.pc.in b/scripts/libpng.pc.in
index 3ee7186d..1892cd31 100644
--- a/scripts/libpng.pc.in
+++ b/scripts/libpng.pc.in
@@ -5,6 +5,6 @@ includedir=@includedir@/libpng12
 
 Name: libpng
 Description: Loads and saves PNG files
-Version: 1.2.50
+Version: 1.2.51beta01
 Libs: -L${libdir} -lpng12
 Cflags: -I${includedir}
diff --git a/scripts/makefile.32sunu b/scripts/makefile.32sunu
index 2127b23d..aed0bacf 100644
--- a/scripts/makefile.32sunu
+++ b/scripts/makefile.32sunu
@@ -11,7 +11,7 @@
 # Library name:
 LIBNAME=libpng12
 PNGMAJ = 0
-PNGMIN = 1.2.50
+PNGMIN = 1.2.51beta01
 PNGVER = $(PNGMAJ).$(PNGMIN)
 
 # Shared library names:
diff --git a/scripts/makefile.64sunu b/scripts/makefile.64sunu
index e1566d41..1f07cbcc 100644
--- a/scripts/makefile.64sunu
+++ b/scripts/makefile.64sunu
@@ -11,7 +11,7 @@
 # Library name:
 LIBNAME=libpng12
 PNGMAJ = 0
-PNGMIN = 1.2.50
+PNGMIN = 1.2.51beta01
 PNGVER = $(PNGMAJ).$(PNGMIN)
 
 # Shared library names:
diff --git a/scripts/makefile.aix b/scripts/makefile.aix
index e23716eb..b0e37886 100644
--- a/scripts/makefile.aix
+++ b/scripts/makefile.aix
@@ -23,7 +23,7 @@ LN_SF = ln -f -s
 
 LIBNAME=libpng12
 PNGMAJ = 0
-PNGMIN = 1.2.50
+PNGMIN = 1.2.51beta01
 PNGVER = $(PNGMAJ).$(PNGMIN)
 
 prefix=/usr/local
diff --git a/scripts/makefile.beos b/scripts/makefile.beos
index 82464e7f..0c7cce09 100644
--- a/scripts/makefile.beos
+++ b/scripts/makefile.beos
@@ -11,7 +11,7 @@
 # Library name:
 LIBNAME=libpng12
 PNGMAJ = 0
-PNGMIN = 1.2.50
+PNGMIN = 1.2.51beta01
 PNGVER = $(PNGMAJ).$(PNGMIN)
 
 # Shared library names:
diff --git a/scripts/makefile.cegcc b/scripts/makefile.cegcc
index 1aff52e3..775e8e88 100644
--- a/scripts/makefile.cegcc
+++ b/scripts/makefile.cegcc
@@ -23,7 +23,7 @@
 
 VERMAJ = 1
 VERMIN = 2
-VERMIC = 50
+VERMIC = 51
 VER = $(VERMAJ).$(VERMIN).$(VERMIC)
 NAME = libpng
 PACKAGE = $(NAME)-$(VER)
diff --git a/scripts/makefile.cygwin b/scripts/makefile.cygwin
index 9826a3cb..d181a343 100644
--- a/scripts/makefile.cygwin
+++ b/scripts/makefile.cygwin
@@ -77,7 +77,7 @@ CFLAGS= $(strip $(MINGW_CCFLAGS) $(addprefix -I,$(ZLIBINC)) \
 LIBNAME = libpng12
 PNGMAJ = 0
 CYGDLL = 12
-PNGMIN = 1.2.50
+PNGMIN = 1.2.51beta01
 PNGVER = $(PNGMAJ).$(PNGMIN)
 
 SHAREDLIB=cygpng$(CYGDLL).dll
diff --git a/scripts/makefile.darwin b/scripts/makefile.darwin
index 2edb8d7a..c5ca6e53 100644
--- a/scripts/makefile.darwin
+++ b/scripts/makefile.darwin
@@ -22,7 +22,7 @@ ZLIBINC=../zlib
 # Library name:
 LIBNAME = libpng12
 PNGMAJ = 12
-PNGMIN = 1.2.50
+PNGMIN = 1.2.51beta01
 PNGVER = $(PNGMAJ).$(PNGMIN)
 
 # Shared library names:
diff --git a/scripts/makefile.dec b/scripts/makefile.dec
index e4b46afa..6868cf5d 100644
--- a/scripts/makefile.dec
+++ b/scripts/makefile.dec
@@ -8,7 +8,7 @@
 
 # Library name:
 PNGMAJ = 0
-PNGMIN = 1.2.50
+PNGMIN = 1.2.51beta01
 PNGVER = $(PNGMAJ).$(PNGMIN)
 LIBNAME = libpng12
 
diff --git a/scripts/makefile.elf b/scripts/makefile.elf
index b93d2cbf..cf825ed0 100644
--- a/scripts/makefile.elf
+++ b/scripts/makefile.elf
@@ -16,7 +16,7 @@
 # Library name:
 LIBNAME = libpng12
 PNGMAJ = 0
-PNGMIN = 1.2.50
+PNGMIN = 1.2.51beta01
 PNGVER = $(PNGMAJ).$(PNGMIN)
 
 # Shared library names:
diff --git a/scripts/makefile.gcmmx b/scripts/makefile.gcmmx
index 24ed729e..4da9d26a 100644
--- a/scripts/makefile.gcmmx
+++ b/scripts/makefile.gcmmx
@@ -17,7 +17,7 @@
 # Library name:
 LIBNAME = libpng12
 PNGMAJ = 0
-PNGMIN = 1.2.50
+PNGMIN = 1.2.51beta01
 PNGVER = $(PNGMAJ).$(PNGMIN)
 
 # Shared library names:
diff --git a/scripts/makefile.hp64 b/scripts/makefile.hp64
index 562aa84b..a3eeb488 100644
--- a/scripts/makefile.hp64
+++ b/scripts/makefile.hp64
@@ -21,7 +21,7 @@ ZLIBINC=/opt/zlib/include
 # Library name:
 LIBNAME = libpng12
 PNGMAJ = 0
-PNGMIN = 1.2.50
+PNGMIN = 1.2.51beta01
 PNGVER = $(PNGMAJ).$(PNGMIN)
 
 # Shared library names:
diff --git a/scripts/makefile.hpgcc b/scripts/makefile.hpgcc
index bdf79599..b53ac470 100644
--- a/scripts/makefile.hpgcc
+++ b/scripts/makefile.hpgcc
@@ -11,7 +11,7 @@
 # Library name:
 LIBNAME = libpng12
 PNGMAJ = 0
-PNGMIN = 1.2.50
+PNGMIN = 1.2.51beta01
 PNGVER = $(PNGMAJ).$(PNGMIN)
 
 # Shared library names:
diff --git a/scripts/makefile.hpux b/scripts/makefile.hpux
index 9edc23ad..ef2372d7 100644
--- a/scripts/makefile.hpux
+++ b/scripts/makefile.hpux
@@ -21,7 +21,7 @@ ZLIBINC=/opt/zlib/include
 # Library name:
 LIBNAME = libpng12
 PNGMAJ = 0
-PNGMIN = 1.2.50
+PNGMIN = 1.2.51beta01
 PNGVER = $(PNGMAJ).$(PNGMIN)
 
 # Shared library names:
diff --git a/scripts/makefile.linux b/scripts/makefile.linux
index 1db8deac..95736332 100644
--- a/scripts/makefile.linux
+++ b/scripts/makefile.linux
@@ -10,7 +10,7 @@
 # Library name:
 LIBNAME = libpng12
 PNGMAJ = 0
-PNGMIN = 1.2.50
+PNGMIN = 1.2.51beta01
 PNGVER = $(PNGMAJ).$(PNGMIN)
 
 # Shared library names:
diff --git a/scripts/makefile.mingw b/scripts/makefile.mingw
index 99539c49..591b3ddb 100644
--- a/scripts/makefile.mingw
+++ b/scripts/makefile.mingw
@@ -81,7 +81,7 @@ CFLAGS= $(strip $(MINGW_CCFLAGS) $(addprefix -I,$(ZLIBINC)) \
 LIBNAME = libpng12
 PNGMAJ = 0
 MINGDLL = 12
-PNGMIN = 1.2.50
+PNGMIN = 1.2.51beta01
 PNGVER = $(PNGMAJ).$(PNGMIN)
 
 SHAREDLIB=libpng$(MINGDLL).dll
diff --git a/scripts/makefile.ne12bsd b/scripts/makefile.ne12bsd
index 7bd2300d..4b964a5d 100644
--- a/scripts/makefile.ne12bsd
+++ b/scripts/makefile.ne12bsd
@@ -17,7 +17,7 @@ INCSDIR=${LOCALBASE}/include/libpng12
 
 LIB=	png12
 SHLIB_MAJOR=	0
-SHLIB_MINOR=	1.2.50
+SHLIB_MINOR=	1.2.51beta01
 SRCS=	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.netbsd b/scripts/makefile.netbsd
index d8466fa3..918dbb8c 100644
--- a/scripts/makefile.netbsd
+++ b/scripts/makefile.netbsd
@@ -17,7 +17,7 @@ INCSDIR=${LOCALBASE}/include
 
 LIB=	png
 SHLIB_MAJOR=	3
-SHLIB_MINOR=	1.2.50
+SHLIB_MINOR=	1.2.51beta01
 SRCS=	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.nommx b/scripts/makefile.nommx
index a6d9ad59..1f1b603b 100644
--- a/scripts/makefile.nommx
+++ b/scripts/makefile.nommx
@@ -10,7 +10,7 @@
 # Library name:
 LIBNAME = libpng12
 PNGMAJ = 0
-PNGMIN = 1.2.50
+PNGMIN = 1.2.51beta01
 PNGVER = $(PNGMAJ).$(PNGMIN)
 
 # Shared library names:
diff --git a/scripts/makefile.openbsd b/scripts/makefile.openbsd
index 443cc5f5..df6e36bf 100644
--- a/scripts/makefile.openbsd
+++ b/scripts/makefile.openbsd
@@ -11,7 +11,7 @@ LIBDIR=	${PREFIX}/lib
 MANDIR= ${PREFIX}/man/cat
 
 SHLIB_MAJOR=	0
-SHLIB_MINOR=	1.2.50
+SHLIB_MINOR=	1.2.51beta01
 
 LIB=	png
 SRCS=	png.c pngerror.c pngget.c pngmem.c pngpread.c \
diff --git a/scripts/makefile.sco b/scripts/makefile.sco
index c734b04d..bab68fb0 100644
--- a/scripts/makefile.sco
+++ b/scripts/makefile.sco
@@ -12,7 +12,7 @@
 # Library name:
 LIBNAME = libpng12
 PNGMAJ = 0
-PNGMIN = 1.2.50
+PNGMIN = 1.2.51beta01
 PNGVER = $(PNGMAJ).$(PNGMIN)
 
 # Shared library names:
diff --git a/scripts/makefile.sggcc b/scripts/makefile.sggcc
index 76f9fcb2..e562043f 100644
--- a/scripts/makefile.sggcc
+++ b/scripts/makefile.sggcc
@@ -9,7 +9,7 @@
 # Library name:
 LIBNAME=libpng12
 PNGMAJ = 0
-PNGMIN = 1.2.50
+PNGMIN = 1.2.51beta01
 PNGVER = $(PNGMAJ).$(PNGMIN)
 
 # Shared library names:
diff --git a/scripts/makefile.sgi b/scripts/makefile.sgi
index 34a76ee8..d13f0a5c 100644
--- a/scripts/makefile.sgi
+++ b/scripts/makefile.sgi
@@ -9,7 +9,7 @@
 # Library name:
 LIBNAME=libpng12
 PNGMAJ = 0
-PNGMIN = 1.2.50
+PNGMIN = 1.2.51beta01
 PNGVER = $(PNGMAJ).$(PNGMIN)
 
 # Shared library names:
diff --git a/scripts/makefile.so9 b/scripts/makefile.so9
index 49f32423..c09e5d18 100644
--- a/scripts/makefile.so9
+++ b/scripts/makefile.so9
@@ -11,7 +11,7 @@
 
 # Library name:
 PNGMAJ = 0
-PNGMIN = 1.2.50
+PNGMIN = 1.2.51beta01
 PNGVER = $(PNGMAJ).$(PNGMIN)
 LIBNAME = libpng12
 
diff --git a/scripts/makefile.solaris b/scripts/makefile.solaris
index 852c6d90..dd8c1fee 100644
--- a/scripts/makefile.solaris
+++ b/scripts/makefile.solaris
@@ -11,7 +11,7 @@
 # Library name:
 LIBNAME = libpng12
 PNGMAJ = 0
-PNGMIN = 1.2.50
+PNGMIN = 1.2.51beta01
 PNGVER = $(PNGMAJ).$(PNGMIN)
 
 # Shared library names:
diff --git a/scripts/makefile.solaris-x86 b/scripts/makefile.solaris-x86
index 16e2dc21..3b475366 100644
--- a/scripts/makefile.solaris-x86
+++ b/scripts/makefile.solaris-x86
@@ -11,7 +11,7 @@
 # Library name:
 LIBNAME = libpng12
 PNGMAJ = 0
-PNGMIN = 1.2.50
+PNGMIN = 1.2.51beta01
 PNGVER = $(PNGMAJ).$(PNGMIN)
 
 # Shared library names:
diff --git a/scripts/png32ce.def b/scripts/png32ce.def
index d2349274..06d612dc 100644
--- a/scripts/png32ce.def
+++ b/scripts/png32ce.def
@@ -5,7 +5,7 @@
 LIBRARY lpngce
 
 EXPORTS
-;Version 1.2.50
+;Version 1.2.51beta01
   png_build_grayscale_palette  @1
   png_check_sig        @2
   png_chunk_error      @3
diff --git a/scripts/pngos2.def b/scripts/pngos2.def
index 5fe8938f..40a65c6e 100644
--- a/scripts/pngos2.def
+++ b/scripts/pngos2.def
@@ -2,7 +2,7 @@
 ; PNG.LIB module definition file for OS/2
 ;----------------------------------------
 
-; Version 1.2.50
+; Version 1.2.51beta01
 
 LIBRARY		PNG
 DESCRIPTION	"PNG image compression library for OS/2"
diff --git a/scripts/pngw32.def b/scripts/pngw32.def
index cca91e18..cec3a352 100644
--- a/scripts/pngw32.def
+++ b/scripts/pngw32.def
@@ -5,7 +5,7 @@
 LIBRARY
 
 EXPORTS
-;Version 1.2.50
+;Version 1.2.51beta01
   png_build_grayscale_palette  @1
   png_check_sig        @2
   png_chunk_error      @3