--- a/src/internet/model/udp-l4-protocol.cc	Sun Dec 15 09:00:57 2013 +0100
+++ b/src/internet/model/udp-l4-protocol.cc	Sun Dec 15 09:26:02 2013 +0100
@@ -403,7 +403,7 @@
   for (Ipv6EndPointDemux::EndPointsI endPoint = endPoints.begin ();
        endPoint != endPoints.end (); endPoint++)
     {
-      (*endPoint)->ForwardUp (packet->Copy (), header, udpHeader.GetSourcePort ());
+      (*endPoint)->ForwardUp (packet->Copy (), header, udpHeader.GetSourcePort (), interface);
     }
   return IpL4Protocol::RX_OK;
 }