Agreed - Jesse, can you work up a patch that generates a clean import
error when _multiprocessing.SemLock can't be defined (due to
HAVE_SEM_OPEN=0 or a single-threaded build), adds test_multiprocessing
to the expected skips for FreeBSD and OpenBSD, and updates the
multiprocessing docs to note the restriction to systems with a working
sem_open() implementation?

Improving the *BSD and single-threaded build compatibility of the
multiprocessing package will just have to be high on the to-do list for
2.6.1.

This may also be worth mentioning in the release notes - Barry's call on
that one.