[boost] [config] BOOST_HAS_NRVO not defined for VC++ 8.0 and later?

Looking at config_info results, BOOST_HAS_NRVO doesn't appear to be defined for VC++ 8.0 and later. But see http://msdn2.microsoft.com/en-us/library/ms364057(VS.80).aspx. According to that, 8.0 and later does support the named return value optimization. What am I missing:-? --Beman