--- Cbc/src/CbcEventHandler.hpp.orig	2007-08-10 12:18:20.000000000 -0400
+++ Cbc/src/CbcEventHandler.hpp	2011-07-29 06:16:23.000000000 -0400
@@ -43,6 +43,7 @@
 */
 
 #include <map>
+#include <cstddef>
 
 /* May well already be declared, but can't hurt. */