A few things seemed to have changed with Trac once I dist-upgraded Trac on Lenny.

ScriptAlias /~sburke/skynet06 /usr/share/trac/cgi-bin/trac.cgi

/usr/share/trac/cgi-bin/trac.cgi didn't exit.

dpkg -L trac | grep cgi This gave, amongst other results: /usr/share/pyshared/trac/web/cgi_frontend.py

Replacement line of code: ScriptAlias /~sburke/skynet06 /usr/share/pyshared/trac/web/cgi_frontend.py

chmod 755 /usr/share/pyshared/trac/web/cgi_frontend.py

Another error 500 from Apache. su - sburke trac-admin /home/sburke/sustainabilityportal upgrade

Worked.

Ref: http://www.landschoff.net/blog/2009/01/trac-hosted-on-debian-unstable-lighty/