diff --git a/include/boost/type_traits/is_enum.hpp b/include/boost/type_traits/is_enum.hpp
index ce74a03..c913975 100644
--- a/include/boost/type_traits/is_enum.hpp
+++ b/include/boost/type_traits/is_enum.hpp
@@ -52,7 +52,7 @@ struct is_class_or_union
 template <typename T>
 struct is_class_or_union
 {
-# if BOOST_WORKAROUND(BOOST_MSVC, < 1300) || BOOST_WORKAROUND(__BORLANDC__, <= 0x570)// we simply can't detect it this way.
+# if BOOST_WORKAROUND(BOOST_MSVC, < 1300) || BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x581))// we simply can't detect it this way.
     BOOST_STATIC_CONSTANT(bool, value = false);
 # else
     template <class U> static ::boost::type_traits::yes_type is_class_or_union_tester(void(U::*)(void));