For those of us that feel strongly that email should be a reliable transport medium.

[Matt Kettler]

Hmm, that's a great way to convince people to join your cause.. start off
with a flame before anyone even replies.

Sigh.

Feel free to develop a patch and use it, but beware of the implications for
your ability to exchange mail with others. I for one take a strong stance
against broken MTAs and at times am forced to start 550ing servers that are
puking on my network when the admins will not correct their servers.

We have a difference of opinion, and that's fine, but keep in mind that
your opinion regarding the "reliability" of email may affect the
reliability of your ability to send mail in the first place.

I'd encourage you to actually try do this some other way than using
MailScanner.. Using a tool with deep MTA layer integrations will allow you
to 550 the message before delivery. You're now meeting your needs for
notifying legitimate senders, AND you're not brokenly puking on bystanders.
It's not something MailScanner can do, but so what? You needs encompass
something that MailScanner cannot do properly.