Hello,
could anyone tell me excactly how Microsoft Outlook 2003 handles the
MIME mediatype "message/rfc822"? The reason I am asking is because I
am currently working on a gateway to convert mail from a custom format
to the rfc2822/rfc2045-2049 specification(s).

In this custom format, it is entirely possible for a mail message to
have whole mail messages attached. It seemed like this would be easily
solved by using the message/rfc822-type to include the entire mail,
but this turned out to be a problem if the attatched mail was itself a
MIME multipart-message. In that case, Outlook simply refuses to list
the incoming mail message at all. Now this was frustrating as,
according to the spec, a message/rfc822-object is allowed to be a
"full blown" MIME-message despite what the name might suggest. To make
sure there was nothing wrong with the generated mail message, I also
tried importing it into several other clients with success, so it
seems like this problem is Outlook-related. An example of such a
message is included below.

I would appreciate any help or suggestions with this, as I don't
really know how to proceed.

#Start mail-example (boundaries renamed to slightly enhance
readability):

Priority: normal
Original-Encoded-Information-Types: iso(1) (0) mhs(10021) ipms(7) (1)
(0)
basic(1), iso(1) (0) mhs(10021) ipms(7) (1) (0) us-ansi-
x3.4-1968(6),
iso(1) (0) mhs(10021) ipms(7) (1) (0) iso-8859-1(100)
Date: Tue, 13 Mar 2007 13:57:00 +0100 (W. Europe Standard Time)
Delivery-Date: Tue, 13 Mar 2007 13:57:00 +0100 (W. Europe Standard
Time)
To:
From:
Message-ID: 0039-0703131357*/@MHS
Subject: Fwd: Attached mail
Importance: normal
MIME-Version: 1.0 (produced by XOmail V14.1.5)
Content-Type: multipart/mixed;
boundary="outer_boundary"

This is a multi-part message in MIME format.

--outer_boundary
Content-Type: text/plain
Content-Transfer-Encoding: 7bit

Bp forwarded mail

--outer_boundary
Content-Type: message/rfc822
Content-Transfer-Encoding: 7bit

Priority: normal
Original-Encoded-Information-Types: Undefined
Date: Tue, 13 Mar 2007 13:56:00 +0100 (W. Europe Standard Time)
Delivery-Date: Tue, 13 Mar 2007 13:56:00 +0100 (W. Europe Standard
Time)
To:
From:
Message-ID: 0038-0703131356*/@MHS
Subject: Attached mail
Importance: normal
Content-Type: multipart/mixed;
boundary="inner_boundary"
MIME-Version: 1.0 (produced by XOmail V14.1.5)

This is a multi-part message in MIME format.

--inner_boundary
Content-Type: text/plain
Content-Transfer-Encoding: 7bit

Bodypart 1, attached mail

--inner_boundary
Content-Type: text/plain
Content-Disposition: inline
Content-Transfer-Encoding: 7bit

Bodypart 2, attached mail

--inner_boundary--

--outer_boundary--

#End mail-example