Re: Mime-Version in message/rfc822 encapsulated messages

My take on it is that if you see MIME-Version in a message/rfc822 part,
it is a MIME message.   If you don't, it is an RFC 822 message.  What do
you do if you don't see MIME-Version, but you do see Content-type?  Who
knows?  I recommend that, for consistency, you do the same thing you do
if you see Content-type but not MIME-Version at the top-level. 
Obviously MIME can't specify anything at all about this case....