Yes i believe it is unrelated to any recent change.
I can reproduce both behaviors on my OS X 10.4 dual core mac using
Python 2.5.1.
Python 2.3 on the mac appears to get stuck in a loop when run stand
alone but gets a memory access fault when run under gdb.
python 2.4.4 seems to hang most of the time.
(all behaviors are possible i expect, i just ran it by hand under
several versions a few times)
The systems i ran it on when reporting the bug was SMP. As with many
threading bugs it might be easier to reproduce on SMP systems but i
haven't checked.