Yes, what you want/need is maildrop. I'm not a linux guru or expert, and maildrop can seem a tad daunting at first to set up.
It does take alot of patience to install, configure, and set up and get working with the Toaster (unless you're an aforementioned expert/guru). But I did manage to do all of the above, and it now does everything I need it to do - and is exactly what you want. What really helped me alot was installing the Squirrelmail add-in called "serversidefilter". It works with qmail+maildrop to add an adequate web interface to SM to add any kind of filtering rule to your maildrop file (usually .mailfilter in the qmail Mailbox dir). That package didn't work for me as installed, and I had to slightly modify the PHP to get it to work just right, but it did (good thing I do know PHP very well). So, qmail+maildrop+serversidefilter works well - even in multi-virtual domain envirnments - SSF simply adds a "Mail Filter" option in SM.. works like a charm. One note - maildrop recently adopted PCRE for regular expressions - I don't believe SSF is set up to write the .mailfilter rules using PCRE, so you might have to install/configure maildrop to use the old regular expression engine. Good luck, -Hank
