Date: Mon, 08 Jan 1996 09:28:27 -0500
From: John C Klensin <klensin@MAIL1.RESTON.MCI.NET>
Subject: Re: "be liberal in what you accept" considered harmful
To: RANDY@MPA15AB.MV.UNISYS.COM
Cc: drums@cs.utk.edu
Message-id: <2.2.16.19960108142827.41ffbca8@mail1.reston.mci.net>
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At 21:59 96.01.05 +0000, RANDY@MPA15AB.MV.UNISYS.COM wrote:
>O2 5 Jan 1996 18:54:18 -0500, John Gardiner Myers <jgm+@CMU.EDU> wrote:
>
>> "Be liberal in what you accept" can actually be a quite harmful
>> practice.  It's use papers over problems which otherwise would be
>> noticed and fixed.
>...
>This is a good point, but if someone implements a new mail system
>today, and rejects messages that do not conform to the standards, it
>will be seen as unable to interoperate.  Wbat's a software developer
>to do?

Be very smart about what you are doing.  If what comes in is incorrect, and
you guess at what it was intended to mean, you will sometimes get it wrong.
When that results in mail delivery to the wrong mailbox, you will end up in
more trouble than if you had rejected the stuff.

I see a transition problem getting back to where we should have been, but
basically agree with John -- the history of senders claiming that receivers
are broken because they aren't liberal enough to accept the garbage the
senders deal out has really been a big contributor the the mess we have today.

Speaking of which, Randy, your host or gateway changes every instance of
    mailbox@dom.ain
into 
    mailbox%dom.ain@MVDNS1.MV-oc.Unisys.COM
This certainly violates the spirit of the rules and can be argued to violate
the letter of them.  Can you get it fixed?

    john