Drupal CMS is an open source web Content Management System which allows users to publish web content, organize discussion communities, run blogs, collaborate on projects, etc.

http://drupal.org/

Jeremy Andrews has added SURBL support to Drupal via the spam_surbl module, which is written in PHP:

http://drupal.org/node/11104

Here is his announcement about it:

http://kerneltrap.org/mailarchive/3/message/31327/thread

Cheers,

Jeff C.