% diagram 4

\verbatim
From: <??me>Message Agent \<<me>>
To: <reply-to|from>
Fcc: +rcvtrip
Fcc: <??fcc><fcc>
Subject: <??subject>BEEP! Re: <subject>
Subject: <!subject>BEEP!
In-reply-to: <??date><??message-id>Your message of <date>.
	     <message-id>
In-reply-to: <??date><!message-id>Your message of <date>.
--------

    This is an automatic reply.  Feel free to send additional mail, as only
    this one notice will be generated.

    I am attending the USENIX Summer '85 conference in Portland, Oregon.
    I expect to be reading mail again on the 16th of June.

/mtr
?endverbatim