Training SpamAssassin

Gentleones, Anyone have a clue how to train SpamAssassin for the following server configuration? Here's the deal: my primary domain server (in Indiana) receives mail for me and redirects it to my secondary server (in Connecticut) where it is Exim'd, SpamAssassined, Exim'd and redirected back via AMS to the primary server in Indiana. (Long story short: the primary server uses WebSTAR 5 and it doesn't do jack except rule-based spam filtering, so it redirects all of the mail to my OSX Server server where the full weight and might of SA can stun and awe the spam.) Eventually, I POP into the primary server and retrieve it all, spam included. (I'm not really ready to bounce anything--I've been getting spam with scores as low as 2.5 which is on par with stuff real people send me--hence the desire to train it.) Entourage takes stuff with "**** SPAM..." and files it away for me on my non-server Mac. Lately, I've been getting LOTS of spam that barely rates a score.... Sad, really. So, that presents me with two challenges/questions: 1) How do I get the batch of E-mails, presuming I can get them out as a bunch of text files or something, to the right place on the OSXS server? And where do they go? Or maybe I can forward them to some useful account on the server? And how do I tell SA to learn what's good and bad, misidentified, etc., if it's a file or AMS E-mail? (As best I can tell, AMS is incompatible with the SA training because it keeps a closed mail database.) 2) Do I have to clean out all the SpamAssassin-inserted lines detailing the rules report before training, or is the SA training function smart enough to ignore that stuff? 3) Is Bayesian filtering on--and present, come to think of it--automatically in SA? (Just making sure I'm not barking up the wrong tree.) Thanks, all, Bill