--- a/src/internet-node/i-ipv4-impl.cc	Thu May 10 18:33:52 2007 +0200
+++ b/src/internet-node/i-ipv4-impl.cc	Thu May 10 20:19:26 2007 +0200
@@ -21,14 +21,13 @@
 #include "i-ipv4-impl.h"
 #include "ipv4.h"
 #include "ns3/assert.h"
+#include "ns3/net-device.h"
 
 namespace ns3 {
 
-IIpv4Impl::IIpv4Impl (Ipv4 *ipv4)
+IIpv4Impl::IIpv4Impl (Ptr<Ipv4> ipv4)
   : m_ipv4 (ipv4)
-{
-  m_ipv4->Ref ();
-}
+{}
 IIpv4Impl::~IIpv4Impl ()
 {
   NS_ASSERT (m_ipv4 == 0);
@@ -36,7 +35,6 @@
 void 
 IIpv4Impl::DoDispose (void)
 {
-  m_ipv4->Unref ();
   m_ipv4 = 0;
 }
 
@@ -90,7 +88,7 @@
   return m_ipv4->RemoveRoute (i);
 }
 uint32_t 
-IIpv4Impl::AddInterface (NetDevice *device)
+IIpv4Impl::AddInterface (Ptr<NetDevice> device)
 {
   return m_ipv4->AddInterface (device);
 }