--- a/src/internet-node/ipv4-interface.cc	Sun Aug 12 16:27:42 2007 +0200
+++ b/src/internet-node/ipv4-interface.cc	Sun Aug 12 16:28:29 2007 +0200
@@ -40,18 +40,19 @@
 Ipv4Interface::~Ipv4Interface ()
 {}
 
+void
+Ipv4Interface::DoDispose (void)
+{
+  m_netdevice = 0;
+  Object::DoDispose ();
+}
+
 Ptr<NetDevice>
 Ipv4Interface::GetDevice (void) const
 {
   return m_netdevice;
 }
 
-Ptr<TraceResolver>
-Ipv4Interface::CreateTraceResolver (void)
-{
-  return DoCreateTraceResolver ();
-}
-
 void 
 Ipv4Interface::SetAddress (Ipv4Address a)
 {