parsing an mbox file without imap?

I have an mbox mailbox on a linux server that I need to open and
parse, message by message, looking for content via PHP. However, for
whatever reason, my hosting provider has not compiled PHP with IMAP
support.

Does anyone have anything written that I can download and use (free
would be nice, heh) to parse my mailbox looking for keywords and
delete/expunge/forward/autoreply based on what I find?

Doesn't need to be super fast for processing speed as I'm the only one
using it and wil only run it once or twice per day on a few MB of
Email. I just don't want to reinvent the wheel if someone out there
has what I'm looking for.

google@w98.us

-id