diff --git a/src/simulator/timer-impl.h b/src/simulator/timer-impl.h
index 346b457fc..bba3fa552 100644
--- a/src/simulator/timer-impl.h
+++ b/src/simulator/timer-impl.h
@@ -25,13 +25,6 @@
 
 namespace ns3 {
 
-template <typename T>
-struct TimerTraits
-{
-  typedef typename TypeTraits<typename TypeTraits<T>::ReferencedType>::NonConstType StoredType;
-  typedef const StoredType &ParameterType;
-};
-
 class TimerImpl
 {
 public:  
@@ -89,6 +82,15 @@ struct TimerImplSix : public TimerImpl
 };
 
 
+
+template <typename T>
+struct TimerTraits
+{
+  typedef typename TypeTraits<typename TypeTraits<T>::ReferencedType>::NonConstType StoredType;
+  typedef const StoredType &ParameterType;
+};
+
+
 template <typename FN>
 TimerImpl *
 MakeTimerImpl (FN fn)