--- a/src/internet-stack/udp-socket-impl.cc	Thu Oct 23 11:50:45 2008 -0700
+++ b/src/internet-stack/udp-socket-impl.cc	Thu Oct 23 11:51:15 2008 -0700
@@ -345,6 +345,7 @@
           m_udp->Send (p->Copy (), addri, bcast,
                        m_endPoint->GetLocalPort (), port);
           NotifyDataSent (p->GetSize ());
+          NotifySend (GetTxAvailable ());
         }
       NS_LOG_LOGIC ("Limited broadcast end.");
       return p->GetSize();
@@ -355,6 +356,7 @@
       m_udp->Send (p->Copy (), ipv4->GetAddress (localIfIndex), dest,
 		   m_endPoint->GetLocalPort (), port);
       NotifyDataSent (p->GetSize ());
+      NotifySend (GetTxAvailable ());
       return p->GetSize();;
     }
   else

--- a/src/node/packet-socket.cc	Thu Oct 23 11:50:45 2008 -0700
+++ b/src/node/packet-socket.cc	Thu Oct 23 11:51:15 2008 -0700
@@ -329,6 +329,7 @@
   if (!error)
     {
       NotifyDataSent (p->GetSize ());
+      NotifySend (GetTxAvailable ());
     }
 
   if (error)