diff -up CEGUI-0.6.2/include/CEGUIBase.h~ CEGUI-0.6.2/include/CEGUIBase.h
--- CEGUI-0.6.2/include/CEGUIBase.h~ 2008-02-11 15:38:27.000000000 +0100
+++ CEGUI-0.6.2/include/CEGUIBase.h 2011-02-13 20:06:29.477851548 +0100
@@ -33,6 +33,7 @@
#ifndef _CEGUIBase_h_
#define _CEGUIBase_h_
+#include <cstddef>
#include <cassert>
// bring in configuration options