--- IMG_png.c.orig	2013-03-06 16:00:15.308563360 +0100
+++ IMG_png.c	2013-03-06 16:02:06.680563289 +0100
@@ -453,7 +453,8 @@
 	/* Allocate the SDL surface to hold the image */
 	Rmask = Gmask = Bmask = Amask = 0 ;
 	num_channels = lib.png_get_channels(png_ptr, info_ptr);
-	if ( color_type != PNG_COLOR_TYPE_PALETTE ) {
+	if ( color_type != PNG_COLOR_TYPE_PALETTE
+	  && color_type != PNG_COLOR_TYPE_GRAY ) {
 #if SDL_BYTEORDER == SDL_LIL_ENDIAN
 			Rmask = 0x000000FF;
 			Gmask = 0x0000FF00;