--- a/examples/realtime/realtime-udp-echo.cc	Fri Aug 20 12:17:19 2010 -0700
+++ a/examples/realtime/realtime-udp-echo.cc	Fri Oct 01 09:19:36 2010 +0200
@@ -113,6 +113,7 @@ 
   // Now, do the actual simulation.
   //
   NS_LOG_INFO ("Run Simulation.");
+  Simulator::Stop (Seconds(10.));
   Simulator::Run ();
   Simulator::Destroy ();
   NS_LOG_INFO ("Done.");
--- a/src/simulator/realtime-simulator-impl.cc	Fri Aug 20 12:17:19 2010 -0700
+++ a/src/simulator/realtime-simulator-impl.cc	Fri Oct 01 09:19:36 2010 +0200
@@ -427,27 +427,22 @@ 
   m_running = true;
   m_synchronizer->SetOrigin (m_currentTs);
 
-  for (;;) 
+  while (!m_stop) 
     {
-      bool done = false;
+      bool process = false;
 
       {
         CriticalSection cs (m_mutex);
-        //
-        // In all cases we stop when the event list is empty.  If you are doing a 
-        // realtime simulation and you want it to extend out for some time, you must
-        // call StopAt.  In the realtime case, this will stick a placeholder event out
-        // at the end of time.
-        //
-        if (m_stop || m_events->IsEmpty ())
+        
+	if (!m_events->IsEmpty ())
           {
-            done = true;
+            process = true;
           }
       }
 
-      if (done)
+      if (!process)
         {
-          break;
+          continue;
         }
 
       ProcessOneEvent ();