--- ./gd_png.c.orig	2007-06-14 14:51:41.000000000 -0500
+++ ./gd_png.c	2010-02-12 01:43:36.000000000 -0600
@@ -149,7 +149,7 @@
 	return NULL;
   }
 
-	if (!png_check_sig (sig, 8)) { /* bad signature */
+	if (!(png_sig_cmp(sig, 0, 8) == 0)) { /* bad signature */
     	return NULL;		/* bad signature */
 	}