[Martin v. Loewis]
My guess is that 2.1.2 will compile fine with whatever expat installation Tim currently has, if it does, pyexpat will certainly work correctly (or: as good as it did in 2.1.1).
It changes the structure of the distribution, though: 2.1 Windows Python shipped with xmlparse.dll and xmltok.dll, 2.2 with neither of those but with a single expat.dll instead. Regardless of whether "it works" for Python, I don't think a bugfix release is the time to change the *set* of DLLs we ship. The MSVC project files on the 2.1 branch also have no idea what to do with the current expat setup, and last-second changes just multiply if I fight that too (the 2.1 PCbuild README would also need to be changed; etc). 2.2 is better here, but the old expat setup wasn't "a bug"; people who want the new setup should upgrade to 2.2, where it was first introduced.