I just noticed that exception analysis in Winpdb is broken since September, when I made it compatible with Python 3.0. In case you are interested the fix is available in the repository which you can pull if you install Mercurial (Source Control Management System).
To pull the latest version of Winpdb from the repository do the following:
hg init hg pull http://winpdb.org/cgi-bin/hgweb.cgi hg update
If no bugs are reported I will soon release the fix officially.
Note that Python 2.6 and Python 3.0 seem to report the wrong line in exception tracebacks.