Here is a sample delivery status notification message from Courier. Notice that both "relay" and "failure" notifications for the same message are consolidated as one notice. Courier offers complete support for the DSN SMTP extensions, as specified by RFC 1894.
Return-Path:
Received: from localhost (localhost [127.0.0.1]) (RFC1894)
by relay1.example.com; Mon, 05 Jul 1999 14:55:42 -0400
From: "Courier mail server at relay1.example.com" <@>
To: perftest1@relay1.example.com
Subject: NOTICE: mail delivery status.
Mime-Version: 1.0
Content-Type: multipart/report; report-type=delivery-status;
boundary="=_courier_0"
Content-Transfer-Encoding: 8bit
Message-ID: <courier.3780FFAE.000062AE@relay1.example.com>
Date: Mon, 05 Jul 1999 14:55:42 -0400
This is a MIME-formatted message. If you see this text it means that your
E-mail software does not support MIME-formatted messages.
--=_courier_0
Content-Transfer-Encoding: 7bit
Content-Type: text/plain; charset=us-ascii
This is a delivery status notification from relay1.example.com,
running the Courier mail server, version 0.10.
The original message was received on Mon, 05 Jul 1999 14:55:26 -0400
from localhost (localhost [127.0.0.1])
---------------------------------------------------------------------------
MESSAGE DELIVERED TO A MAIL GATEWAY
You requested a delivery acknowledgement (a return receipt) for the
following recipients of your E-mail message. Unfortunately, your message
has been transferred to a remote mail system running older software that
that is not be capable of generating standard delivery acknowledgements.
Unless your message is eventually returned undeliverable, you may not
receive any further delivery notices for the following addresses:
<test2@relay2.example.com>:
[127.0.0.1]:
<<< 250 ok 931200942 qp 25258
---------------------------------------------------------------------------
UNDELIVERABLE MAIL
Your message to the following recipients cannot be delivered:
<nosuchuser@relay2.example.com>:
[127.0.0.1]:
>>> RCPT TO:<nosuchuser@relay2.example.com>
<<< 550 Sorry, no mailbox here by that name. (#5.1.1)
---------------------------------------------------------------------------
If your message was also sent to additional recipients, their delivery
status is not included in this report. You may or may not receive
other delivery status notifications for additional recipients.
The original message follows as a separate attachment.
--=_courier_0
Content-Type: message/delivery-status
Content-Transfer-Encoding: 7bit
Reporting-MTA: dns; relay1.example.com
Arrival-Date: Mon, 05 Jul 1999 14:55:26 -0400
Received-From-MTA: unknown; localhost (uid 501)
Final-Receipient: rfc822; nosuchuser@relay2.example.com
Action: failed
Status: 5.0.0
Remote-MTA: dns; [127.0.0.1]
Diagnostic-Code: smtp; 550 Sorry, no mailbox here by that name. (#5.1.1)
Final-Receipient: rfc822; test2@relay2.example.com
Action: relayed
Status: 2.0.0
Remote-MTA: dns; [127.0.0.1]
Diagnostic-Code: smtp; 250 ok 931200942 qp 25258
--=_courier_0
Content-Type: message/rfc822
Content-Transfer-Encoding: 8bit
Received: from localhost (localhost [127.0.0.1]) (uid 501)
by relay1.example.com; Mon, 05 Jul 1999 14:55:26 -0400
From: "test daemon" <perftest1@example.com>
To: perftest1@example.com
Subject: 8bit test
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 8bit
Message-ID: <courier.3780FF9E.00006296@relay1.example.com>
Date: Mon, 05 Jul 1999 14:55:26 -0400
¡
test 0
--=_courier_0--