diff --git a/include/boost/python/detail/indirect_traits.hpp b/include/boost/python/detail/indirect_traits.hpp
index 170f3662..752cd7d2 100644
--- a/include/boost/python/detail/indirect_traits.hpp
+++ b/include/boost/python/detail/indirect_traits.hpp
@@ -280,9 +280,8 @@ struct is_pointer_to_function
 struct false_helper1
 {
     template <class T>
-    struct apply
+    struct apply : mpl::false_
     {
-        BOOST_STATIC_CONSTANT(bool, value = false);
     };
 };
 
@@ -300,22 +299,13 @@ struct true_helper1
         BOOST_STATIC_CONSTANT(
             bool, value
             = sizeof(reference_to_const_helper(t)) == sizeof(inner_yes_type));
+        typedef mpl::bool_<value> type;
     };
 };
 
 template <bool ref = true>
 struct is_reference_to_const_helper1 : true_helper1
 {
-#   if 0
-    template <class T>
-    struct apply
-    {
-        static T t;
-        BOOST_STATIC_CONSTANT(
-            bool, value
-            = sizeof(reference_to_const_helper(t)) == sizeof(inner_yes_type));
-    };
-#   endif 
 };
 
 template <>
@@ -331,7 +321,6 @@ struct is_reference_to_const
 };
 
 
-
 template <bool ref = true>
 struct is_reference_to_non_const_helper1
 {