diff -uNr warmux-11.04.orig/src/graphic/surface.cpp warmux-11.04/src/graphic/surface.cpp
--- warmux-11.04.orig/src/graphic/surface.cpp	2011-09-19 09:26:52.392650465 +0200
+++ warmux-11.04/src/graphic/surface.cpp	2011-09-19 09:26:19.417648189 +0200
@@ -25,6 +25,7 @@
 #include <SDL_image.h>
 #include <SDL_rotozoom.h>
 #include <png.h>
+#include <zlib.h>
 
 #include "graphic/surface.h"
 #include "tool/math_tools.h"