diff -r 56b16bcd3afc src/simulator/timer.cc
--- a/src/simulator/timer.cc	Mon May 18 11:06:26 2009 +0100
+++ b/src/simulator/timer.cc	Mon May 18 14:49:33 2009 +0200
@@ -24,7 +24,7 @@
 namespace ns3 {
 
 Timer::Timer ()
-  : m_flags (0),
+  : m_flags (CHECK_ON_DESTROY),
     m_delay (FemtoSeconds (0)),
     m_event (),
     m_impl (0)