So... in the last weeks I've been playing with Trac to setup it inside my company. We have a Multiple Project environment and I was trying to get it working under a name like this: "projects.foo.bar".

After some fight and after read the really nice mod_rewrite documentation (1.3 here) and the really cool URL Rewriting Guide (1.3 here) I get this setup to work:

Alias /trac "/usr/share/trac/htdocs/"

RewriteEngine on
RewriteRule ^/trac(/?.*)$                       - [L]
RewriteRule ^/+$                                /index.cgi [L]

RewriteCond /var/www/projects/$1                -d
RewriteRule ^/([[:alnum:]]+)(/?.*)              /trac.cgi$2 [S=1,E=TRAC_ENV:/var/www/projects/$1]
RewriteRule ^/(.*)                              /index.cgi

The rest of the tricks are in the TracMultipleProject page, anyway, looks like that the new versions of Trac are using mod_pythons and some new resources, really good stuff. Congratualtions to Trac Team! I'm using this setup with Apache2 in a Debian Sarge environment. Enjoy it! :o)