The tests don't work under py3k, for some reason I can't figure out.
There's the following error and then the tests hang:

test_acct (test.test_ftplib.TestTLS_FTPClassMixin) ... Exception in
thread Thread-31:
Traceback (most recent call last):
  File "/home/antoine/py3k/__svn__/Lib/threading.py", line 521, in
_bootstrap_inner
    self.run()
  File "/home/antoine/py3k/__svn__/Lib/test/test_ftplib.py", line 214,
in run
    asyncore.loop(timeout=0.1, count=1)
  File "/home/antoine/py3k/__svn__/Lib/asyncore.py", line 210, in loop
    poll_fun(timeout, map)
  File "/home/antoine/py3k/__svn__/Lib/asyncore.py", line 136, in poll
    r, w, e = select.select(r, w, e, timeout)
select.error: (9, 'Bad file descriptor')