Running a debug python from the py3k branch on my windows 7 machine, 64 
bit, test_multiprocessing hangs in the _TestZZZNumberOfObjects test.

I don't know this module, but I did a little digging:
The main process is in the gc.collec() causing some manager object to 
call a _decref() method, which is initiating a socket connection to a 
child process (I presume.)  This is spinning endlessly because the 
connection is constantly refused.

The child processes don't have any sockets open (according to the 
resource monitor) and when I look at the state they are in, the are 
stuck waiting for a ReadFile to succeed.  The python traceback appears 
to be (innermost first, line numbers approximate:)
queues.py:349
pool.py:45
process.py:83
process.py:215
forking.py:326