Hallo, this is the same as a patch already applied to boost/detail/utf8_codecvt_facet.hpp and as one I just submitted for boost/iostreams/detail/config/codecvt.hpp . Cheers, Nicola Musatti ******Index: codecvt_null.hpp =================================================================== RCS file: /cvsroot/boost/boost/boost/archive/codecvt_null.hpp,v retrieving revision 1.13 diff -d -u -r1.13 codecvt_null.hpp --- codecvt_null.hpp 12 Dec 2005 15:22:02 -0000 1.13 +++ codecvt_null.hpp 8 Apr 2006 15:04:18 -0000 @@ -26,7 +26,7 @@ using ::mbstate_t; #elif defined(__QNXNTO__) using std::mbstate_t; - #elif defined(BOOST_DINKUMWARE_STDLIB) + #elif defined(BOOST_DINKUMWARE_STDLIB) && ! defined(__BORLANDC__) using ::mbstate_t; #elif defined(__SGI_STL_PORT) #elif defined(BOOST_NO_STDC_NAMESPACE)