diff --git a/include/boost/function.hpp b/include/boost/function.hpp
index f4556fe..62c47b8 100644
--- a/include/boost/function.hpp
+++ b/include/boost/function.hpp
@@ -323,12 +323,6 @@ namespace boost {
         };
       };
 
-      template<typename T1, typename T2>
-      struct is_not_same
-      {
-  	    BOOST_STATIC_CONSTANT(bool, value = !(is_same<T1, T2>::value));
-      };
-
 #ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
       template<bool GetIt, typename Traits> 
       struct get_arg1_type