Mine

Alias /viewvc /usr/lib/python2.5/site-packages/viewvc/bin/mod_python/viewvc-mp.py

<Directory /usr/lib/python2.5/site-packages/viewvc/bin/mod_python>
    AddHandler python-program .py
    PythonHandler handler
    ReWriteEngine on
    ReWriteBase /viewvc
    ReWriteCond %{REQUEST_URI} viewvc\.cgi
    RewriteRule viewvc\.cgi/(.*) /viewvc/$1 [R]
</Directory>