Subject: Undelivered Mail Returned to Sender
From: [email-masked] (Mail Delivery System)
To: [email-masked]
Date: Mon, 23 Apr 2012 16:30:04 +0100 (BST)

This is the mail system at host admin1.example.co.uk.

I'm sorry to have to inform you that your message could not
be delivered to one or more recipients. It's attached below.

For further assistance, please send mail to <postmaster>

If you do so, please include this problem report. You can
delete your own text from the attached returned message.

                   The mail system

<[email-masked]>: host fwd2.hosts.co.uk[85.233.160.24] said: 550 Spamming
    not allowed (in reply to end of DATA command)

Subject: foo
From: Fred Bloggs <[email-masked]>
To: john smith <[email-masked]>
Date: Mon, 23 Apr 2012 16:30:03 +0100

HTML