> This is on Linux with latest py3k branch:
> 
> test test_urllibnet failed -- Traceback (most recent call last):
>   File "/home/cartman/Sources/py3k/Lib/test/test_urllibnet.py", line
> 145, in test_bad_address
>     urllib.urlopen, "http://www.python.invalid./")
> AssertionError: IOError not raised by urlopen

Is this on the trunk?
For me, test_bad_address test passes for test_urllibnet.py
- This is on Fedora Core 2, with the just checkout trunk of py3k.

That said, there are problems with email package instances ( which was replaced for mimetools). Shall work out for patch.

======================================================================
FAIL: test_info (__main__.urlopenNetworkTests)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "test_urllibnet.py", line 91, in test_info
    "object returned by 'info' is not an instance of "
AssertionError: object returned by 'info' is not an instance of
email.message.Message

======================================================================
FAIL: test_header (__main__.urlretrieveNetworkTests)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "test_urllibnet.py", line 184, in test_header
    "header is not an instance of email.message.Message")
AssertionError: header is not an instance of email.message.Message

----------------------------------------------------------------------