[Mimedefang] Block mail by subject

[Les Mikesell]

On Wed, 2004-03-24 at 11:45, WBrown at e1b.org wrote:

> At least you were rejecting, not dropping.  Amazing how many places think 
> it's acceptable to just drop.
> 

If you sent a lot of messages (say from support at your_organization,
or webmaster) you would quickly realize that notification is
worse.  Every pc that has your address on a message in the
inbox is likely to get a virus and send thousands of copies
with your address forged as the From:.  When any other system
rejects with notification, you get it - and everyone who depends
on you to keep their PC running will call you every time they
get one of these...


> The other thing that was totally amazing is how many spam filtering 
> solution there are that will accept a message, let the SMTP connection 
> close, and then scan/filter the email.  They have no choice but to beleive 
> the sender information if they wish to return a failure message.  For 
> people like that, I have this very nice bridge for sale in NYC.

If you reject with an SMTP 5xx, you simply force the previous
SMTP relay to do exactly the same thing.  Unless it is the
first hop doing the scanning, all you have is the forged
header information to construct the error reply, and PC's
almost always use a relay.

---
  Les Mikesell
   les at futuresource.com