php.net documentation framework availability?

I've long been impressed with the documentation framework at php.net, and I'm thinking about implementing something similar for my own project. I don't have time to build something from scratch, though, so I'm wondering: Is the php.net documentation system available for others to use on their own sites? Or is there anything out there that would give a similar result? I'd like something I can plug into a server that would let me start writing directly, similar to the PHP CMSs you see everywhere now. Thanks for the help. -- Joel Konkle-Parker