diff --git a/include/boost/type_traits/config.hpp b/include/boost/type_traits/config.hpp
index 2ea48a4..cdb4ac6 100644
--- a/include/boost/type_traits/config.hpp
+++ b/include/boost/type_traits/config.hpp
@@ -24,7 +24,7 @@
 #   define BOOST_TT_DECL /**/
 #endif
 
-# if (defined(__MWERKS__) && __MWERKS__ >= 0x3000) || (defined(BOOST_MSVC) && (BOOST_MSVC > 1301)) || defined(__EDG_VERSION__) || (defined(__GNUC__) && (__GNUC__ >= 3)) || defined(__DMC__) || defined(BOOST_NO_COMPILER_CONFIG)
+# if (defined(__MWERKS__) && __MWERKS__ >= 0x3000) || (defined(BOOST_MSVC) && (BOOST_MSVC > 1301)) || defined(__EDG_VERSION__) || (defined(__GNUC__) && (__GNUC__ >= 3)) || defined(__DMC__) || ( defined(__IBMCPP__) && (__IBMCPP__ >= 600 ) ) || defined(BOOST_NO_COMPILER_CONFIG)
 #   define BOOST_TT_HAS_CONFORMING_IS_CLASS_IMPLEMENTATION
 #endif