diff --git a/ANNOUNCE b/ANNOUNCE
index 5ba09e1..eaa87e1 100644
--- a/ANNOUNCE
+++ b/ANNOUNCE
@@ -1,5 +1,5 @@
 
-Libpng 1.6.4beta02 - August 21, 2013
+Libpng 1.6.4beta02 - August 30, 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.
@@ -31,7 +31,10 @@
   Delay calling png_init_filter_functions() until a row with nonzero filter
     is found.
 
-Version 1.6.4beta02 [August 21, 2013]
+Version 1.6.4beta02 [August 30, 2013]
+  Fixed inconsistent conditional compilation of png_chunk_unknown_handling()
+    prototype, definition, and usage.  Made it depend on
+    PNG_HANDLE_AS_UNKNOWN_SUPPORTED everywhere.
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit
diff --git a/CHANGES b/CHANGES
index e431a83..07d7063 100644
--- a/CHANGES
+++ b/CHANGES
@@ -4623,7 +4623,10 @@
   Delay calling png_init_filter_functions() until a row with nonzero filter
     is found.
 
-Version 1.6.4beta02 [August 21, 2013]
+Version 1.6.4beta02 [August 30, 2013]
+  Fixed inconsistent conditional compilation of png_chunk_unknown_handling()
+    prototype, definition, and usage.  Made it depend on
+    PNG_HANDLE_AS_UNKNOWN_SUPPORTED everywhere.
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit
diff --git a/LICENSE b/LICENSE
index 896ecd5..b639ef8 100644
--- a/LICENSE
+++ b/LICENSE
@@ -10,7 +10,7 @@
 
 This code is released under the libpng license.
 
-libpng versions 1.2.6, August 15, 2004, through 1.6.4beta02, August 21, 2013, are
+libpng versions 1.2.6, August 15, 2004, through 1.6.4beta02, August 30, 2013, are
 Copyright (c) 2004, 2006-2013 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 @@
 
 Glenn Randers-Pehrson
 glennrp at users.sourceforge.net
-August 21, 2013
+August 30, 2013
diff --git a/README b/README
index f70721d..c53b666 100644
--- a/README
+++ b/README
@@ -1,4 +1,4 @@
-README for libpng version 1.6.4beta02 - August 21, 2013 (shared library 16.0)
+README for libpng version 1.6.4beta02 - August 30, 2013 (shared library 16.0)
 See the note about version numbers near the top of png.h
 
 See INSTALL for instructions on how to install libpng.
diff --git a/libpng-manual.txt b/libpng-manual.txt
index 6cb3d24..09d922a 100644
--- a/libpng-manual.txt
+++ b/libpng-manual.txt
@@ -1,6 +1,6 @@
 libpng-manual.txt - A description on how to use and modify libpng
 
- libpng version 1.6.4beta02 - August 21, 2013
+ libpng version 1.6.4beta02 - August 30, 2013
  Updated and distributed by Glenn Randers-Pehrson
  <glennrp at users.sourceforge.net>
  Copyright (c) 1998-2013 Glenn Randers-Pehrson
@@ -11,7 +11,7 @@
 
  Based on:
 
- libpng versions 0.97, January 1998, through 1.6.4beta02 - August 21, 2013
+ libpng versions 0.97, January 1998, through 1.6.4beta02 - August 30, 2013
  Updated and distributed by Glenn Randers-Pehrson
  Copyright (c) 1998-2013 Glenn Randers-Pehrson
 
@@ -5229,7 +5229,7 @@
 
 XVI. Y2K Compliance in libpng
 
-August 21, 2013
+August 30, 2013
 
 Since the PNG Development group is an ad-hoc body, we can't make
 an official declaration.
diff --git a/libpng.3 b/libpng.3
index df8de8f..c244e67 100644
--- a/libpng.3
+++ b/libpng.3
@@ -1,4 +1,4 @@
-.TH LIBPNG 3 "August 21, 2013"
+.TH LIBPNG 3 "August 30, 2013"
 .SH NAME
 libpng \- Portable Network Graphics (PNG) Reference Library 1.6.4beta02
 .SH SYNOPSIS
@@ -504,7 +504,7 @@
 .SH LIBPNG.TXT
 libpng-manual.txt - A description on how to use and modify libpng
 
- libpng version 1.6.4beta02 - August 21, 2013
+ libpng version 1.6.4beta02 - August 30, 2013
  Updated and distributed by Glenn Randers-Pehrson
  <glennrp at users.sourceforge.net>
  Copyright (c) 1998-2013 Glenn Randers-Pehrson
@@ -515,7 +515,7 @@
 
  Based on:
 
- libpng versions 0.97, January 1998, through 1.6.4beta02 - August 21, 2013
+ libpng versions 0.97, January 1998, through 1.6.4beta02 - August 30, 2013
  Updated and distributed by Glenn Randers-Pehrson
  Copyright (c) 1998-2013 Glenn Randers-Pehrson
 
@@ -5734,7 +5734,7 @@
 
 .SH XVI. Y2K Compliance in libpng
 
-August 21, 2013
+August 30, 2013
 
 Since the PNG Development group is an ad-hoc body, we can't make
 an official declaration.
@@ -6014,7 +6014,7 @@
 
 Thanks to Frank J. T. Wojcik for helping with the documentation.
 
-Libpng version 1.6.4beta02 - August 21, 2013:
+Libpng version 1.6.4beta02 - August 30, 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).
 
@@ -6037,7 +6037,7 @@
 
 This code is released under the libpng license.
 
-libpng versions 1.2.6, August 15, 2004, through 1.6.4beta02, August 21, 2013, are
+libpng versions 1.2.6, August 15, 2004, through 1.6.4beta02, August 30, 2013, are
 Copyright (c) 2004,2006-2007 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
@@ -6136,7 +6136,7 @@
 
 Glenn Randers-Pehrson
 glennrp at users.sourceforge.net
-August 21, 2013
+August 30, 2013
 
 .\" end of man page
 
diff --git a/libpngpf.3 b/libpngpf.3
index 5073dd2..040f674 100644
--- a/libpngpf.3
+++ b/libpngpf.3
@@ -1,4 +1,4 @@
-.TH LIBPNGPF 3 "August 21, 2013"
+.TH LIBPNGPF 3 "August 30, 2013"
 .SH NAME
 libpng \- Portable Network Graphics (PNG) Reference Library 1.6.4beta02
 (private functions)
diff --git a/png.5 b/png.5
index ac5b104..151b20f 100644
--- a/png.5
+++ b/png.5
@@ -1,4 +1,4 @@
-.TH PNG 5 "August 21, 2013"
+.TH PNG 5 "August 30, 2013"
 .SH NAME
 png \- Portable Network Graphics (PNG) format
 .SH DESCRIPTION
diff --git a/png.c b/png.c
index f5c5d9d..2588b13 100644
--- a/png.c
+++ b/png.c
@@ -768,13 +768,13 @@
 #else
 #  ifdef __STDC__
    return PNG_STRING_NEWLINE \
-     "libpng version 1.6.4beta02 - August 21, 2013" PNG_STRING_NEWLINE \
+     "libpng version 1.6.4beta02 - August 30, 2013" PNG_STRING_NEWLINE \
      "Copyright (c) 1998-2013 Glenn Randers-Pehrson" PNG_STRING_NEWLINE \
      "Copyright (c) 1996-1997 Andreas Dilger" PNG_STRING_NEWLINE \
      "Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc." \
      PNG_STRING_NEWLINE;
 #  else
-      return "libpng version 1.6.4beta02 - August 21, 2013\
+      return "libpng version 1.6.4beta02 - August 30, 2013\
       Copyright (c) 1998-2013 Glenn Randers-Pehrson\
       Copyright (c) 1996-1997 Andreas Dilger\
       Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.";
@@ -855,7 +855,7 @@
    return PNG_HANDLE_CHUNK_AS_DEFAULT;
 }
 
-#ifdef PNG_READ_UNKNOWN_CHUNKS_SUPPORTED
+#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
 int /* PRIVATE */
 png_chunk_unknown_handling(png_const_structrp png_ptr, png_uint_32 chunk_name)
 {
@@ -864,7 +864,7 @@
    PNG_CSTRING_FROM_CHUNK(chunk_string, chunk_name);
    return png_handle_as_unknown(png_ptr, chunk_string);
 }
-#endif /* READ_UNKNOWN_CHUNKS */
+#endif /* HANDLE_AS_UNKNOWN */
 #endif /* SET_UNKNOWN_CHUNKS */
 
 #ifdef PNG_READ_SUPPORTED
diff --git a/png.h b/png.h
index 9c53e0a..c2fda9c 100644
--- a/png.h
+++ b/png.h
@@ -1,7 +1,7 @@
 
 /* png.h - header file for PNG reference library
  *
- * libpng version 1.6.4beta02 - August 21, 2013
+ * libpng version 1.6.4beta02 - August 30, 2013
  * Copyright (c) 1998-2013 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.)
@@ -11,7 +11,7 @@
  * 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 1.6.4beta02 - August 21, 2013: Glenn
+ *   libpng versions 0.97, January 1998, through 1.6.4beta02 - August 30, 2013: Glenn
  *   See also "Contributing Authors", below.
  *
  * Note about libpng version numbers:
@@ -210,7 +210,7 @@
  *
  * This code is released under the libpng license.
  *
- * libpng versions 1.2.6, August 15, 2004, through 1.6.4beta02, August 21, 2013, are
+ * libpng versions 1.2.6, August 15, 2004, through 1.6.4beta02, August 30, 2013, are
  * Copyright (c) 2004, 2006-2013 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:
@@ -322,7 +322,7 @@
  * Y2K compliance in libpng:
  * =========================
  *
- *    August 21, 2013
+ *    August 30, 2013
  *
  *    Since the PNG Development group is an ad-hoc body, we can't make
  *    an official declaration.
@@ -390,7 +390,7 @@
 /* Version information for png.h - this should match the version in png.c */
 #define PNG_LIBPNG_VER_STRING "1.6.4beta02"
 #define PNG_HEADER_VERSION_STRING \
-     " libpng version 1.6.4beta02 - August 21, 2013\n"
+     " libpng version 1.6.4beta02 - August 30, 2013\n"
 
 #define PNG_LIBPNG_VER_SONUM   16
 #define PNG_LIBPNG_VER_DLLNUM  16
diff --git a/pngconf.h b/pngconf.h
index 544df52..e8f8681 100644
--- a/pngconf.h
+++ b/pngconf.h
@@ -1,7 +1,7 @@
 
 /* pngconf.h - machine configurable file for libpng
  *
- * libpng version 1.6.4beta02 - August 21, 2013
+ * libpng version 1.6.4beta02 - August 30, 2013
  *
  * Copyright (c) 1998-2013 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
diff --git a/pngpriv.h b/pngpriv.h
index 4d8051f..fb15134 100644
--- a/pngpriv.h
+++ b/pngpriv.h
@@ -1431,15 +1431,13 @@
     * just skips the chunk or errors out if it is critical.
     */
 
-#ifdef PNG_READ_UNKNOWN_CHUNKS_SUPPORTED
-#ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED
+#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
 PNG_INTERNAL_FUNCTION(int,png_chunk_unknown_handling,
     (png_const_structrp png_ptr, png_uint_32 chunk_name),PNG_EMPTY);
    /* Exactly as the API png_handle_as_unknown() except that the argument is a
     * 32-bit chunk name, not a string.
     */
-#endif
-#endif /* PNG_READ_UNKNOWN_CHUNKS_SUPPORTED */
+#endif /* PNG_HANDLE_AS_UNKNOWN_SUPPORTED */
 #endif /* PNG_READ_SUPPORTED */
 
 /* Handle the transformations for reading and writing */
diff --git a/pngrutil.c b/pngrutil.c
index ff215b2..8ad299f 100644
--- a/pngrutil.c
+++ b/pngrutil.c
@@ -2764,7 +2764,6 @@
 
    png_debug(1, "in png_handle_unknown");
 
-#ifdef PNG_READ_UNKNOWN_CHUNKS_SUPPORTED
    /* NOTE: this code is based on the code in libpng-1.4.12 except for fixing
     * the bug which meant that setting a non-default behavior for a specific
     * chunk would be ignored (the default was always used unless a user
@@ -2776,16 +2775,15 @@
     * This is just an optimization to avoid multiple calls to the lookup
     * function.
     */
-#  ifndef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
-#     ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED
-         keep = png_chunk_unknown_handling(png_ptr, png_ptr->chunk_name);
-#     endif
+#  ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+   keep = png_chunk_unknown_handling(png_ptr, png_ptr->chunk_name);
 #  endif
 
    /* One of the following methods will read the chunk or skip it (at least one
     * of these is always defined because this is the only way to switch on
     * PNG_READ_UNKNOWN_CHUNKS_SUPPORTED)
     */
+#ifdef PNG_READ_UNKNOWN_CHUNKS_SUPPORTED
 #  ifdef PNG_READ_USER_CHUNKS_SUPPORTED
       /* The user callback takes precedence over the chunk keep value, but the
        * keep value is still required to validate a save of a critical chunk.
@@ -2893,7 +2891,7 @@
 
          png_crc_finish(png_ptr, length);
       }
-#  endif
+#  endif /* PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED */
 
 #  ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
       /* Now store the chunk in the chunk list if appropriate, and if the limits
diff --git a/projects/vstudio/readme.txt b/projects/vstudio/readme.txt
index a554027..da4e9f6 100644
--- a/projects/vstudio/readme.txt
+++ b/projects/vstudio/readme.txt
@@ -1,7 +1,7 @@
 
 VisualStudio instructions
 
-libpng version 1.6.4beta02 - August 21, 2013
+libpng version 1.6.4beta02 - August 30, 2013
 
 Copyright (c) 1998-2010 Glenn Randers-Pehrson
 
diff --git a/projects/vstudio/zlib.props b/projects/vstudio/zlib.props
index 2826ca2..ab9aebb 100644
--- a/projects/vstudio/zlib.props
+++ b/projects/vstudio/zlib.props
@@ -2,7 +2,7 @@
 <!--
  * zlib.props - location of zlib source
  *
- * libpng version 1.6.4beta02 - August 21, 2013
+ * libpng version 1.6.4beta02 - August 30, 2013
  *
  * Copyright (c) 1998-2011 Glenn Randers-Pehrson
  *
diff --git a/scripts/README.txt b/scripts/README.txt
index e6d6d5c..e471d62 100644
--- a/scripts/README.txt
+++ b/scripts/README.txt
@@ -1,5 +1,5 @@
 
-Makefiles for  libpng version 1.6.4beta02 - August 21, 2013
+Makefiles for  libpng version 1.6.4beta02 - August 30, 2013
 
 pnglibconf.h.prebuilt       =>  Stores configuration settings
  makefile.linux    =>  Linux/ELF makefile
diff --git a/scripts/pnglibconf.h.prebuilt b/scripts/pnglibconf.h.prebuilt
index aee2910..e65b091 100644
--- a/scripts/pnglibconf.h.prebuilt
+++ b/scripts/pnglibconf.h.prebuilt
@@ -2,7 +2,7 @@
 
 /* pnglibconf.h - library build configuration */
 
-/* Libpng version 1.6.4beta02 - August 21, 2013 */
+/* Libpng version 1.6.4beta02 - August 30, 2013 */
 
 /* Copyright (c) 1998-2013 Glenn Randers-Pehrson */