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To: Thomas Dean <tomdean@ix.netcom.com>
cc: questions@FreeBSD.ORG
Subject: Re: undeliverable mail messages 
In-reply-to: Your message of "Sun, 19 Oct 1997 18:53:10 PDT."
             <199710200153.SAA02769@celebris.tddhome> 
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Date: Mon, 20 Oct 1997 23:58:03 +0100
From: Brian Somers <brian@awfulhak.org>
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> I am using sendmail "version.c 8.8.7.3 (Berkeley) 8/3/97", which has
> been working.
> 
> Lately, I have been getting undeliverable mail messages when I cc
> myself.  If I do not cc myself, the mail seems to be delivered OK.  If
> I send mail to myself as tomdean@ix.netcom.com, I get the
> undeliverable message.  If I send mail to myself as tomdean@celebris,
> it works.  I may have changed something, but, I don't remember doing
> it.  Asleep at the wheel?
[.....]
> Oct 19 11:09:24 celebris sendmail[1300]: IAA00342:
> to=tomdean@ix.netcom.com, ctladdr=tomdean (1001/1001), delay=03:07:19,
> xdelay=00:00:55, mailer=esmtp, relay=ixsrs1.ix.netcom.com. [199.
> 182.120.201], stat=Deferred: 451 <tomdean@celebris.tddhome>... Domain
> must resolve

Sounds like you either need to set yourself up with a DNS that 
resolves celebris.tddhome, or (perhaps) using a config like

  http://www.freebsd.org/FAQ/ispmail.html

may resolve things.
-- 
Brian <brian@Awfulhak.org>, <brian@FreeBSD.org>, <bri@OpenBSD.org>
      <http://www.Awfulhak.org>
Don't _EVER_ lose your sense of humour....