For years, Boost.Python has been doing some hacks to work around the fact that a Windows Python distro doesn't include the debug build of the library. http://www.boost.org/libs/python/doc/building.html#variants explains. We wanted to make it reasonably convenient for Windows developers (and our distributed testers) to work with a debug build of the Boost.Python library and of their own code. Having to download the Python source and build the debug DLL was deemed unacceptable. Well, those hacks have run out of road. VC++8 now detects that some of its headers have been #included with _DEBUG and some without, and it will refuse to build anything when it does. We have several new hacks to work around that detection, and I think we _might_ be able to get away with them for one more release. But it's really time to do it right. MS is recommending that we (Boost) start distributing a debug build of the Python DLL with Boost, but Boost really seems like the wrong place to host such a thing. Is there any way Python.org can make a debug build more accessible? Thanks, Dave -- Dave Abrahams Boost Consulting www.boost-consulting.com