[exim] OT: Abusive mailserver

I recently submitted a complaint about a mailing list that kept trying to
send messages to defunct addresses. It always ignored 550 errors and kept
banging away trying to deliver to non-existent recipients several times in
succession. Not surprisingly, this mailserver didn't accept emails to
postmaster and abuse, so I contacted the domain's host who forwarded the
complaint to the company concerned.

I got back a snotty answer from the company that it wasn't their
responsibility to clean their own mailing lists.

I replied that the main issue was the fact that their mailserver was
ignoring 550 errors, in contravention of the RFCs, and bombarding our server
with multiple copies of undeliverable messages.

The reply I got back from them was:

"For your information, our external IT advisers have now adjusted the
settings on our server to prevent a recurrence of the issue that you raised
- although in their view your comments were pedantic in the extreme and no
similar concerns were raised by any other of the recipients of our email."

So there's an IT company out there that thinks it's "extremely pedantic" to
expect mailservers not to ignore 550 errors.

I really wish there was a way to keep people like this off the Internet. Or
was I indeed just being "extremely pedantic"?

- Mark