--- a/src/internet-node/ipv4-interface.h	Wed May 09 19:48:33 2007 +0200
+++ b/src/internet-node/ipv4-interface.h	Wed May 09 23:23:05 2007 -0400
@@ -25,6 +25,7 @@
 
 #include <list>
 #include "ns3/ipv4-address.h"
+#include "ns3/object.h"
 
 namespace ns3 {
 
@@ -61,7 +62,7 @@
  *   - Ipv4Interface::SendTo
  *   - Ipv4Interface::DoCreateTraceResolver
  */
-class Ipv4Interface 
+class Ipv4Interface : public Object
 {
 public:
   /**