Errors-to: owner-drums@CS.UTK.EDU
Message-Id: <199509241029.GAA12979@CS.UTK.EDU>
To: drums@CS.UTK.EDU
From: "Roger Fajman" <RAF@CU.NIH.GOV>
Date:     Sat, 23 Sep 1995  23:40:16 EDT
Subject:  Re:  support for Postmaster address

> Another case: if you send to user@murrawan.cs.mu.oz.au your
> mail will be bounced (murrawan is a terminal server, it has
> no mailer, and never will, still people see people logged in from
> there, and assume it must be a workstation, so send mail there...)
>
> The bounce is done by...
>
>        murrawan IN MX 0 mailbounce
>
> where mailbounce.cs.mu.oz.au is a (non CNAME) alias for a
> host that runs a really trivial mailer that simply bounces
> everything - that is, every RCPT command elicts an error
> response, whatever the address is.   A typical dialog
> follows...

This is the case that the proposed SMTP 521 (I think that's the number)
reply is supposed to handle -- a host that doesn't accept mail at all.
It explicitly says that accepting mail to postmaster isn't required,
since the host doesn't really support mail.  There's an I-D on it under
the mailext WG.