Guys,
Here is an excerpt from a discussion in another NG about MailWasher. I don't know diddley about mail daemons or "550" replies but it does raise some interesting issues if in fact it's violating the ISP AUP.
bill g
#########Excerpt:
I'm going to jump a bit off the topic of your post to throw a slam
against MailWasher - notably the "bounce" feature.
What the "bounce" feature does is absolutely pointless, and in
actuality is causing you to both violate your ISPs' Acceptable Use
Policy, and to mailbomb some innocent user - as well as mailbomb the admin of your ISP who sees all the failed bounces come back to the mailer-daemon.
The bounce feature sends back a *forged* 550 message from
mailer-daemon@yourisp.com - which is completely MEANINGLESS after the mail has already been successfully delivered.
The 550 rejects from a REAL mailer-daemon happen at the time of the MTA transaction between the mail servers. Sending back a 550 Reject 8 hours later when you pop your mail does nothing except verify that you are using the stupid mailwasher "bounce" feature. - The REAL MTA transaction was completed 8 hours earlier, and your address was already VERIFIED as being deliverable to the spammer.
On top of that, the *forged* bounce goes to the person listed in the "from" address header - which 99.9% of the time is forged to be some innocent user at yahoo/hotmail, etc. - or even YOUR OWN ADDRESS.
I started seeing these bounces come back to a mailer-daemon on a server I manage, and after I found out that mailwasher was causing it, I first issued a warning to the user for forging a system account, and then sent an explanitory email to the author of Mailwasher, explaining that he was causing people to violate their ISP AUP. He responded saying that "the bounce feature is extremely effective" -well, what that REALLY translates into is: "It is extremely effective at raising my sales because people love nice-sounding features, regardless of how well they work, or what mayhem they unleash"
Because of the irresponsible attitude of the author, I view mailwasher as a "hostile" program. If you care about reducing mail abuse, (and not getting your account shut down) DUMP mailwasher - By using Mailwasher you are CONTRIBUTING to e-mail abuse.
-gib