[boost] Building from current CVS

I'm trying to build from the current CVS (actually about a week old), and it has some weird problem with creating files and directories. When trying to build with a version of Jam from 1.32, it always falls over trying to create a file or directory, normally mentioning Mkdir1 first. When trying to build the version of Jam that comes with the CVs source, it is able to build jam0.exe, but when it comes time to make bin.ntx86 it fails; and if that directory exists, the jam executable is not created; instead an error about "spawn: No such file or directory" is emittted. I am using vc 7.1. Any ideas for a better way to build the boost libraries?