diff --git a/png.h b/png.h
index bf0239813..6a5309d73 100644
--- a/png.h
+++ b/png.h
@@ -1,7 +1,7 @@
 
 /* png.h - header file for PNG reference library
  *
- * libpng version 1.5.0beta56 - November 21, 2010
+ * libpng version 1.5.0beta56 - November 25, 2010
  * Copyright (c) 1998-2010 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 1.5.0beta56 - November 21, 2010: Glenn
+ *   libpng versions 0.97, January 1998, through 1.5.0beta56 - November 25, 2010: Glenn
  *   See also "Contributing Authors", below.
  *
  * Note about libpng version numbers:
@@ -173,7 +173,7 @@
  *
  * This code is released under the libpng license.
  *
- * libpng versions 1.2.6, August 15, 2004, through 1.5.0beta56, November 21, 2010, are
+ * libpng versions 1.2.6, August 15, 2004, through 1.5.0beta56, November 25, 2010, are
  * Copyright (c) 2004, 2006-2010 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:
@@ -285,7 +285,7 @@
  * Y2K compliance in libpng:
  * =========================
  *
- *    November 21, 2010
+ *    November 25, 2010
  *
  *    Since the PNG Development group is an ad-hoc body, we can't make
  *    an official declaration.
@@ -349,7 +349,7 @@
 /* Version information for png.h - this should match the version in png.c */
 #define PNG_LIBPNG_VER_STRING "1.5.0beta56"
 #define PNG_HEADER_VERSION_STRING \
-     " libpng version 1.5.0beta56 - November 21, 2010\n"
+     " libpng version 1.5.0beta56 - November 25, 2010\n"
 
 #define PNG_LIBPNG_VER_SONUM   15
 #define PNG_LIBPNG_VER_DLLNUM  15
@@ -2044,10 +2044,15 @@ PNG_EXPORT(png_const_bytep,png_get_io_chunk_name,(png_structp png_ptr),,200);
       ((png_uint_32)(*((buf) + 1)) << 16) + \
       ((png_uint_32)(*((buf) + 2)) << 8) + \
       ((png_uint_32)(*((buf) + 3))))
+
+   /* From libpng-1.4.0 until 1.4.4, the png_get_uint_16 macro (but not the
+    * function) incorrectly returned a value of type png_uint_32.
+    */
 #  define png_get_uint_16(buf) \
      ((png_uint_16) \
       (((unsigned int)(*(buf)) << 8) + \
        ((unsigned int)(*((buf) + 1)))))
+
 #  define png_get_int_32(buf) \
      ((png_int_32)((*(buf) & 0x80) \
       ? -((png_int_32)((png_get_uint_32(buf) ^ 0xffffffffL) + 1)) \