🚀 go-pugleaf

    Date: Mon, 17 Nov 86 11:07:45 pst
    From: Scott J. Kramer <sjk at grape.ads.arpa>

    Speaking of mail replies, there's an annoyance related to using a
    REPLY-TO field, which I currently use because the host I'm sending
    from isn't recognized on the Internet.

    When the recipient responds to a message with a REPLY-TO which also
    has CC addresses, the CC's are omitted in the reply; only the REPLY-TO
    address is used.  RFC822 isn't specific about this; it just says "if
    REPLY-TO exists, then the reply should go to the addresses indicated
    in that field and not to the address(es) indicated in the FROM field."

    I'm CC'ing Header-People on this since someone there may know of a way
    to do what I'm trying to do (ie, have CC's get replies if I use
    REPLY-TO).  From what I can tell, the only way is to have a valid FROM
    field.

Reply-To: means send replies to this address.  If there's no Reply-to:
then your mail reader should compose a reply to the union of CC and
From.  If you're sending from a host which for some reason won't
identify itself usefully, specify a From:.  Hopefully your mailer will
set the Sender: field to be the invalid address, ut preserver the
From:.

In other words, gnu emacs is doing the right thing; you should use
From: where you now use Reply-to:.