> > I conjecture that the BAD result in the case of Jean-Christophe's
> > message, #4 above, results from him inserting a non-standard X- header
> > in the signed MIME part. I don't have an explanation for the other BAD
> > results.
> I have rfc822 fresh in my mind. User headers are perfectly legal. They
> only "might later be preempted" (quoting from that 1982 rfc) if their
> name becomes officially accepted or sumesuch.