*** virtual-net-device.cc~	Fri Jun 26 16:49:11 2009
--- virtual-net-device.cc	Wed Jul  8 11:21:29 2009
***************
*** 115,120 ****
--- 115,121 ----
  void VirtualNetDevice::DoDispose()
  {
    NS_LOG_FUNCTION_NOARGS ();
+   m_node=0;
    NetDevice::DoDispose ();
  }