our amavis/postfix/maildrop/dovecot server is good, but we are left a 
wee bit wanting.  here is a (priority ordered) wishlist:

   1. spam scanning may be on a distant machine (amavis/postfix can do this)
   2. if spam scanning is at all delayed, recipients may see unscanned
      messages, perhaps in an imap folder (don't think amavis can do this)
   3. progressively slow down response to a machine failing
      authentication into ssh, imap, or pop
   4. progressively slow down response to a server that sends gobs of spam
   5. spam may be separated into more than one folder based on spaminess
      thresholds separately adjustable by each user (maia/maildrop can
      do this)
   6. if a message is reclassified as spam or nonspam by a user, other
      recipients of messages with identical bodyparts may see the
      reclassified result
   7. if another recipient of similar content again reclassifies a
      message, the prior user may see that
   8. if a user classifies a message before a scan result is obtained,
      it may be removed from the spamscan queue
   9. where various messages contain an identical attachment or
      bodypart, the system is smart enough to refer to a prior scan or
      reclassification result
  10. where various messages contain an identical attachment or
      bodypart, the system is smart enough to store only a single copy,
      eg by hardlinking

are there worthy of mention answers to these wishes?

tia,
greg wm