So here's the deal.
Basically, I am looking for a convenient way to get spam from my Exchange 2010 mail server to my spam filter/proxy (whatever you want to call it) in a mail format for SpamAssassin to do its Bayesian filtering (Maildir or Mbox apparently).
I have created a gateway that filters mail and then passes it through to my Exchange server, as per this tutorial. From the research I have done it should be easy to apply the Bayesian filtering once the mail is in a format that it knows how to use:
sa-learn -mbox --spam ~/mbox/spam ~/mbox/bad-spam
Essentially, SpamAssassin needs a certain number of SPAM and HAM emails to do its thing and was thinking I could have users dump their emails into this public folder.
My initial inclination was to use something like IMAP2mbox and then dumping it into a directory on the SpamAssassin gateway. Therein lies my problem, it seems that this has become tricky to do with Exchange Server 2010 as there is no longer support for IMAP public folders built in.
I am stumped trying to come up with a way to get spam emails from my Exchange server into a format that SpamAssassin can use.
I am guessing there is a similar way to do this, but I'm not sure where to look next.