#1479 USEPRO 3.8: Whether moderators SHOULD retain message-ID

Charles Lindsey raised this back in February 2007, and it hasn't seen 
any comments.

The text in question is currently (as of -12):

   4.  Moderators are encouraged to retain the Message-ID header field
       if it is valid, and also retain the Date header field unless it
       appears to be stale (72 hours or more in the past) for reasons
       understood by the moderator (such as delays in the moderation
       process) in which case they MAY substitute the current date.  Any
       Injection-Date, Injection-Info, or Xref header fields already
       present MUST be removed.

Charles wanted a SHOULD for retaining message-ID. Nobody else commented.

If nobody else comments on the issue, I'll close it as "no support for a 
change".

                    Harald