How about using the USENET keyword of NEWSGROUP: and making that a
replyable field with a higher priority than that of Sender: for
notification/rejection purposes. Not that I intend to redefine the
way that RFC822 works - but if MAs like MAILBOOK are going to be
picky - then I consider it our duty to find a way around it in order
to keep a more efficient distributed-mail-network. yes?
            - Michael Gettes, Boston University
I guess this is meant for Eric since he is the only one responding.