diff --git a/ANNOUNCE b/ANNOUNCE
index bf6522f60..9bc9e707b 100644
--- a/ANNOUNCE
+++ b/ANNOUNCE
@@ -216,6 +216,7 @@ version 1.5.0beta23 [April 29, 2010]
     This makes the installed pnglibconf.h more readable but causes no
     other change.  The intention is that users of libpng will find it
     easier to understand if an API they need is missing.
+  Include png_reset_zstream() in png.c only when PNG_READ_SUPPORTED is defined.
 
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diff --git a/CHANGES b/CHANGES
index 740e19b67..62cc071e2 100644
--- a/CHANGES
+++ b/CHANGES
@@ -2698,6 +2698,7 @@ version 1.5.0beta23 [April 29, 2010]
     This makes the installed pnglibconf.h more readable but causes no
     other change.  The intention is that users of libpng will find it
     easier to understand if an API they need is missing.
+  Include png_reset_zstream() in png.c only when PNG_READ_SUPPORTED is defined.
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit
diff --git a/png.c b/png.c
index b117d64a6..2e005c0b4 100644
--- a/png.c
+++ b/png.c
@@ -1,7 +1,7 @@
 
 /* png.c - location for general purpose libpng functions
  *
- * Last changed in libpng 1.5.0 [April 28, 2010]
+ * Last changed in libpng 1.5.0 [April 29, 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.)
@@ -548,13 +548,13 @@ png_get_copyright(png_structp png_ptr)
 #else
 #  ifdef __STDC__
    return ((png_charp) PNG_STRING_NEWLINE \
-     "libpng version 1.5.0beta23 - April 28, 2010" PNG_STRING_NEWLINE \
+     "libpng version 1.5.0beta23 - April 29, 2010" PNG_STRING_NEWLINE \
      "Copyright (c) 1998-2010 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 ((png_charp) "libpng version 1.5.0beta23 - April 28, 2010\
+      return ((png_charp) "libpng version 1.5.0beta23 - April 29, 2010\
       Copyright (c) 1998-2010 Glenn Randers-Pehrson\
       Copyright (c) 1996-1997 Andreas Dilger\
       Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.");
@@ -618,7 +618,9 @@ png_handle_as_unknown(png_structp png_ptr, png_bytep chunk_name)
    return 0;
 }
 #  endif
+#endif /* defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) */
 
+#ifdef PNG_READ_SUPPORTED
 /* This function, added to libpng-1.0.6g, is untested. */
 int PNGAPI
 png_reset_zstream(png_structp png_ptr)
@@ -627,7 +629,7 @@ png_reset_zstream(png_structp png_ptr)
       return Z_STREAM_ERROR;
    return (inflateReset(&png_ptr->zstream));
 }
-#endif /* defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) */
+#endif /* PNG_WRITE_SUPPORTED */
 
 /* This function was added to libpng-1.0.7 */
 png_uint_32 PNGAPI