spamd and bayes question

[Jeffrey N. Miller]

I want to use Spamassassin with MIMEDefang and Sendmail as a SMTP Gateway.  Can you use spamd/spamc with this method or does it just invoke the script method?  Also, what is the best way to train spamassassin if I have a SPAM dump in MSExchange public folders?  Or is there a better way of training bayes?