Subject: smtpupd-09 still prohibits double-bounces

From: "D. J. Bernstein" <[email-masked]>
Date: 30 Jan 1999 04:57:29 -0000

Modern MTAs send ``double-bounce'' notifications to the local postmaster
when a bounce message is undeliverable.

I originally brought this up in response to

> if this address is null
> ("<>"), the receiver-SMTP MUST NOT send a notification.

and the document editor added an exception. Unfortunately, we still have

> Of course, SMTP servers MUST NOT send notification messages about problems
> transporting notification messages.

and a strange new

> A queuing strategy MUST NOT send error messages in
> response to error messages under any circumstances.

and perhaps more requirements that, thanks to the editor's slip-it-in
policy and the poor structure of smtpupd, I haven't spotted yet.

---Dan