A recent update in boost/test/detail/class_properties.hpp replaces line 163: #ifndef __IBMCPP__ with #if BOOST_WORKAROUND(__IBMCPP__, BOOST_TESTED_AT(600)) I guess this is an error, since the checks are just the opposite. BTW, this change seems to be producing many regressions in Visual Age, all of them reported for boost/test/test_tools.hpp. HTH, Joaquín M López Muñoz Telefónica, Investigación y Desarrollo