diff --git a/include/boost/type_traits/is_signed.hpp b/include/boost/type_traits/is_signed.hpp
index 2d0afac..48facd3 100644
--- a/include/boost/type_traits/is_signed.hpp
+++ b/include/boost/type_traits/is_signed.hpp
@@ -64,7 +64,7 @@ struct is_signed_select_helper<false>
 };
 
 template <class T>
-struct is_signed
+struct is_signed_impl
 {
    typedef ::boost::detail::is_signed_select_helper< ::boost::is_integral<T>::value || ::boost::is_enum<T>::value> selector;
    typedef typename selector::template rebind<T> binder;
@@ -74,7 +74,7 @@ struct is_signed
 
 }
 
-template <class T> struct is_signed : public integral_constant<bool, boost::detail::is_signed<T>::value> {};
+template <class T> struct is_signed : public integral_constant<bool, boost::detail::is_signed_impl<T>::value> {};
 
 #else