Hello, I want to use nanoseconds from boost::posix_time but as stated in the reference, you have to define BOOST_DATE_TIME_POSIX_TIME_STD_CONFIG to make that work. Unfortunatelly I don't have any idea where i have to define that variable in the build process. I build boost 1.47.0 like this on osx snow leopard: ./b2 macosx-version=10.6 link=static address-model=32_64 threading=multi stage So, where do I have to define the discussed variable to enable nanosecond support? Offtopic: I also noticed that adress-model=32_64 does not seem to work since all the produced static libs are x86_64 only.- Any ideas about how to fix that? Thank you!