> > heapq tries to import _heapq but, at this point, the build dir 
> > (such as "build/lib.linux-x86_64-3.2/") hasn't been added to sys.path
> 
> The problem only exists for developers, not for an installation copy
> of Python?

This particular problem indeed (for developers and for buildbots - see
the weird test_heapq failures on some OS X buildbots).

> Another approach is to call required site code earlier (eg. rewrite it
> in C and execute it before loading the locale module).

Indeed, but since it calls sysconfig.get_platform(), I'm not sure how
much code would need to be rewritten in C.