failed mail not returned to sender

[Mark Plotnick]

The USG mailer (mail, rmail, uux) currently gives notification of
failed mail to the sender.  Unfortunately, since it doesn't bother
merging multiple "From" lines, many replies wind up going to
the user "uucp" on a neighboring machine, rather than the person
who really sent the message.  Look in /usr/spool/mail/uucp (or /usr/mail/uucp)
and you too can see these messages.

Moreover, although it says "Letter returned to sender", I never see
any such letter.  If it did include the failed message, at least
I could forward it manually to the correct person.

	Mark