[Spambayes] Any prospect of spambayes working with qmail?

[T. Alexander Popiel]

In message:  <1045167697.5666.764.camel at adamselene.home>
             Nick Holden <nick_holden at ntlworld.com> writes:

>I'm intrigued by the spambayes project, and wondered whether you'd put
>any thought to apps to fit spambayes into the sendmail / qmail end of
>the mail process rather than as an end-user app?

We've discussed similar from time to time, and I think that the
general consensus is that spambayes is poorly suited for such use.

The basic problem is one of defining spam.  In spambayes, the
definition that we use is 'spam is whatever the user says is spam'.
This requires direct user involvement in the training process,
for obvious reason.

Unfortunately, trying to incorporate spambayes into an MTA upstream
of the users presents three problems:

1. An upstream MTA is likely to have multiple users.  If the users
   disagree on what constitutes spam, then the training will be
   inconsistent and spambayes will get confused.

2. An upstream MTA is likely to not have any good facilities for
   users to train through.  About the best that could be hoped for
   would be a web interface similar to pop3proxy... but that's
   rather far outside the scope of an MTA and is unlikely to be
   set up in a way that the users could access it and the spammers
   couldn't.

3. Most of us want to be able to peruse all our mail, even that
   marked as spam, looking for false positives (which frequently
   occur for a short while after starting a new business relationship
   with some vendor on the web).  If an upstream MTA is tossing
   stuff spambayes thinks is spam, then users cannot do this perusal.
   If the upstream MTA is merely marking the email without tossing
   it, then the MTA hasn't gained anything, but has instead spent
   a bunch of cycles on a judgement that could be forged by a
   spammer.

In the end, spambayes makes for a very poor tool to be used by
paternalistic ISPs, precisely because of the user-centric spam
definition that makes it a wonderful tool for individual user
installations.

- Alex