--- a/src/node/ipv4-address.cc	Sat Aug 22 15:38:32 2009 -0700
+++ b/src/node/ipv4-address.cc	Sun Aug 23 14:00:50 2009 -0700
@@ -18,6 +18,7 @@
  * Author: Mathieu Lacage <mathieu.lacage@sophia.inria.fr>
  */
 
+#include <stdlib.h>
 #include "ns3/log.h"
 #include "ipv4-address.h"
 #include "ns3/assert.h"