while trying to link to lib boost md5 i get these errors

I build using make with -l"boost_md5-mgw41-1_34_1.

booost md5 was build using gcc 4.1.2 mingw.

C:/Boost/include/boost-1_34_1/boost/md5.hpp:33: undefined reference to `boost::md5::context::context()'
C:/Boost/include/boost-1_34_1/boost/md5.hpp:33: undefined reference to `boost::md5::context::context()'
C:/Boost/include/boost-1_34_1/boost/md5.hpp:57: undefined reference to `boost::md5::process(void const*, unsigned int, bool)'
C:/Boost/include/boost-1_34_1/boost/md5.hpp:46: undefined reference to `boost::md5::clear()'
C:/Boost/include/boost-1_34_1/boost/md5.hpp:46: undefined reference to `boost::md5::clear()'