--- php/php-src/trunk/ext/gd/libgd/gd_png.c	2009/04/01 16:05:17	278124
+++ php/php-src/trunk/ext/gd/libgd/gd_png.c	2010/01/10 02:13:45	293341
@@ -145,7 +145,7 @@
 		return NULL;
 	}
 
-	if (!png_check_sig (sig, 8)) { /* bad signature */
+	if (png_sig_cmp(sig, 0, 8) != 0) { /* bad signature */
 		return NULL;
 	}