--- ns-2.34/mac/mac-802_11Ext.h	2009-06-14 18:35:44.000000000 +0100
+++ ns-2.34.rasm/mac/mac-802_11Ext.h	2012-09-17 23:57:33.860998370 +0100
@@ -57,6 +57,7 @@
  
 #ifndef ns_mac_80211Ext_h
 #define ns_mac_80211Ext_h
+#include <cstddef>
 #include "marshall.h"
 #include "timer-handler.h"
 #define GET_ETHER_TYPE(x)		GET2BYTE((x))