I've recently hit an issue with pyvenv in Python 3.3.2 that is causing AttributeErrors in other packages on Windows (see https://groups.google.com/forum/?fromgroups#!topic/pylons-discuss/FpOSMDpdvy4).  Here's what I believe is going on:

On Windows, the pyvenv pydoc script has a .py extension - so import finds it instead of the system's pydoc module.  On Linux, the pyvenv pydoc script doesn't have an extension - so import finds the system's pydoc module.

I believe the Windows pyvenv pydoc.py script should be renamed to something like pydocs.py to prevent AttributeErrors.