--- a/src/mobility/mobility-model-notifier.cc	Tue Aug 28 14:32:44 2007 +0200
+++ b/src/mobility/mobility-model-notifier.cc	Tue Aug 28 14:33:53 2007 +0200
@@ -41,7 +41,7 @@
 }
 
 Ptr<TraceResolver> 
-MobilityModelNotifier::GetTraceResolver (void)
+MobilityModelNotifier::GetTraceResolver (void) const
 {
   Ptr<CompositeTraceResolver> resolver = 
     Create<CompositeTraceResolver> ();