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To: "Paul F. Safonov" <spf@news.sable.krasnoyarsk.su>
cc: freebsd-questions@freefall.cdrom.com
Subject: Re: SENDMAIL problem 
In-reply-to: Your message of "Mon, 10 Apr 95 21:10:58 PDT."
             <zGI5WYlixd@news.sable.krasnoyarsk.su> 
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Date: Tue, 11 Apr 1995 10:29:58 PDT
From: Bill Fenner <fenner@parc.xerox.com>
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In message <zGI5WYlixd@news.sable.krasnoyarsk.su> you write:
>There is a problem while processing "Return-Receipt-To".
>The receipt is sent from a zero user (see below).
>Should it be so?

Yes.  MAIL FROM: <> makes it so that the receiving mailer doesn't bother 
trying to bounce the message.  It is part of RFC821.

      ... Of course, server-SMTPs should not send notification
      messages about problems with notification messages.  One way to
      prevent loops in error reporting is to specify a null reverse-path
      in the MAIL command of a notification message.  When such a
      message is relayed it is permissible to leave the reverse-path
      null.  A MAIL command with a null reverse-path appears as follows:

         MAIL FROM:<>

  Bill