[Boost-users] Compile 32 bits on 64 arch how-to ?

Hello, I would like to compile boost on 64 opteron arch but create the libraries in 32 bits mode (using -m32 cxxflags). The reason for that is that i have quite a lot libraries compiled in 32 that i can't port for the moment to 64. I'm not sure how to do that. I read about modifying user.hpp usung the configure script and that is what i did but it still doesn't seem to compile with the -m32 compiler flag. Can anyone help me ?