Quoting Jeff Chan <[EMAIL PROTECTED]>:
SpamAssassin and Exim cannot work together without some other program coordinating them. You're probably going to need to find out what that program is in order to solve things. Any FAQs about SpamAssassin itself may address the coordinating program, but only peripherally. SpamAssassin only scores the messages. It doesn't deliver them and it doesn't control how they're delivered based on that score.
Also if you find the name of the program, you can probably search for the faq for it, SpamAssassin and Exim.
HTH, Jeff C.