--- a/src/common/trailer.cc	Mon Mar 17 14:01:55 2008 -0700
+++ b/src/common/trailer.cc	Mon Mar 17 14:49:52 2008 -0700
@@ -16,4 +16,10 @@
   return tid;
 }
 
+std::ostream & operator << (std::ostream &os, const Trailer &trailer)
+{
+  trailer.Print (os);
+  return os;
+}
+
 } // namespace ns3