Hah! I found the answer in a python mailing list from someone who was having trouble building the python part of boost in conjunction with stlport. Changing my build batch to the following was the key: set stlport-iostream="on" set STLPORT_VERSION="4.6.2" set STLPORT_PATH="C:/" bjam "-sTOOLS=vc7.1-stlport" "-sBUILD=debug release" install Thanks to everyone for their help! Mike _________________________________________________________________ MSN Toolbar provides one-click access to Hotmail from any Web page – FREE download! http://toolbar.msn.click-url.com/go/onm00200413ave/direct/01/