I've followed the doc's 'Static Libraries and Serialization' approach. To move the serialize implementation from the header to the cpp file for my classes in my hierarchy which are serialized through base class pointer. Which runs on MSVC8, after linking with /OPT:NOREF. Unfortunately the BOOST_CLASS_EXPORTxxx facilities appear to be optimized away on gcc/xcode, even though all of the 'strip' settings are off. What approach are others taking to resolve this? Robert's reply to Emil Dotchevski on Sep 25, 2008 suggests that explicitly calling ar.register(static_cast<myType *>(0)); is the only portable way to ensure registration, is this still the case? Should explicit registration be done in combination with or en lieu of BOOST_CLASS_EXPORTxxx? Thanks, Jeff