Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sdd.hp.com!usc!snorkelwacker!bloom-beacon!eru!hagbard!sunic!eric
From: eric@sunic.sunet.se (Eric Thomas SUNET)
Newsgroups: comp.mail.headers
Subject: Re: Wanted: Messed-Up Mail Headers
Message-ID: <2167@sunic.sunet.se>
Date: 28 Sep 90 16:18:05 GMT
References: <1990Sep22.174312.29336@ibmpcug.co.uk> <2016@argus.UUCP> <28292@pasteur.Berkeley.EDU>
Organization: Royal Institute of Technology, Sweden
Lines: 25

In article <28292@pasteur.Berkeley.EDU> jbuck@galileo.berkeley.edu (Joe Buck) writes:
>Kenneth, this is an easy one to solve.  You should be liberal because
>people sometimes screw up, but in a case like the above, either the
>address is standard (so the receiver is in error) or the address is
>non-standard (so the sender is in error).

Or maybe the meaning is undefined, RFC822 is unfortunately not binary. I have a
server which receives requests via mail. I have some sites sending me mail
with two 'From:' fields, as in 'From: Joe@ABC' followed by 'From: Joe@XYZ'
where ABC and XYZ "look" like variations on the same host name to a human
being. My server likes to know who sent the command, so it refuses to process
such messages. The senders complain that their fields are syntactically correct
(which is true, each of the 2 fields is ok), that RFC822 doesn't say you
can't have more than one (which is also true, although it doesn't define the
meaning of that), and that the 2 addresses should point to the same mailbox, I
should just stop being fussy and accept the command, sending the reply to both
addresses. I refuse to do that on the basis that it's not my problem but
theirs, and that if RFC822 intended to allow multiple originating addresses
they would not have disallowed multiple mailbox specifications in the 'From:'
field (when no 'Sender:' is present).

It's no big deal, I just wanted to show that the case is not always as clear
as you said it is...

  Eric