http://bugs.gentoo.org/308741
http://aur.archlinux.org/packages/gtkatlantic/gtkatlantic/libpng14.patch

--- src/readpng.c
+++ src/readpng.c
@@ -33,7 +33,7 @@ gboolean readpng_init(FILE *infile, png_
 	png_uint_32 width, height;
 
 	fread(sig, 1, 8, infile);
-	if (!png_check_sig(sig, 8))
+	if (png_sig_cmp(sig, 0, 8))
 		return FALSE;
 
 	*png_struct = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);