Donovan,

I am currently using qmail + maildrop + SpamAssassin + sql. There are 
many different ways to allow the end user configure there filters. I 
have attached a link to the SpamAssassin Wiki.

http://wiki.apache.org/spamassassin/

also a link to the Web Interfaces:

http://wiki.apache.org/spamassassin/WebUserInterfaces

Hope this helps.

-Mike

Donovan wrote:
> Does anybody have a favorite tool for integrating spam filtering with
> Qmail that provides a web interface to view filtered spam?
>