Loss of Information while mapping an Internet S/MIME Message to X .400.

Hi,

As per draft-ietf-smime-x400transport-07.txt:
"When transporting a CMS-protected message in X.400, the preferred approach
is to
convey the object as X.400 message content. Implementations MUST include the
CMS 
object in the content field of the X.400 message."

However when mapping an Internet S/MIME message to an X.400 Message:
1. The CMS object is placed in the X.400 Message Content (as recommended).
2. The RFC 822 header fields of the Internet message that can be mapped
directly 
   to the X.400 envelope fields are placed in the X.400 Message Envelope.

3. This leaves out the Internet Message header fields that are normally
mapped to 
   the IPM Content Heading fields. In the X.400 Content carrying the CMS
object 
   there are no corresponding fields for them. As a result such fields
apparently 
   cannot be mapped to the X.400 message and will be lost (on conversion
from 
   Internet to X.400 message). Such fields are :
   Subject, From, To, Reply-to, In-reply-to, Message-id, cc, bcc, Sender,
Expiry-
   date, Deferred-delivery-date, Latest-delivery-time, Importance,
Sensitivity, 
   Language and References.
   
How can this loss of information be avoided, what is the recommended way
around 
this particular problem?

The possible workarounds could be:

1. The Internet User Agent constructing an S/MIME message SHOULD place the 
   message content along with these fields into a Message/rfc-822 content
before 
   securing it. This should be done if these fields are desired to be seen
by 
   the receiving user agent (in case the message is to be transported over
an 
   X.400 network.)

   But I found that existing applications like Microsoft Outlook do not
provide 
   an option to perform an Message/rfc-822 wrapping of these fileds.

2. Another solution could be to map the CMS object in an IPMS content,
wherein
   the above fields could then be mapped to the IPMS content heading fields,
and 
   the CMS object could be placed in an appropriate bodypart (ftbp with file
type 
   as smime.p7m). 
   
   But this goes against the recommendation "Implementations generally
SHOULD 
   NOT embed CMS objects within X.400 body parts, but should instead convey
them 
   as content as described in sec. 2.2" of
draft-ietf-smime-x400transport07.txt.

Best Regards
Arun Pandey