[Boost-users] library name for boost 1.36

Hi, I just built boost 1.36 for the mac and all the library names have xgcc40 inserted in the middle, such as libboost_iostreams-xgcc40-mt-1_36.dylib. It breaks my makefiles that contain the option " -lboost_iostreams". Is there a reason for the xgcc40 in this version and not the others, and is there a way to instruct bjam not to include it in the filename. Thank, s