Richard, 'Message-ID' is part of the  set of 'junk' header keywords which
are  normally  removed  (remember  the   30+  lines  headers  of  Ricky's
LISTSERV?). You  might argue that  'Message-ID' is such an  important tag
that you cannot understand how I can call it 'junk', but my definition of
'junk' is 'not  understood by the end user and  not needed for delivery'.
Anyway, you can get the 'Message-ID' back  into your header by means of a
'SET  listname FULLHDR'  (or 'FULLBSMTP'  if you  prefer the  BSMTP-style
headers);  to  make  it  the  default   for  the  list,  you  can  put  a
"Default-Options= FULLHDR<,etc>" in the list header.
 
  Eric