Sendmail DNS strangeness

[Chris Rees]

For about four days now, I've had these emails stuck in my mailqueue,
and I don't understand what the problem is. Sure it says it has a DNS
failure, but what does it mean?


Jan 29 16:03:19 amnesiac sm-mta[38492]: n0RM2Hlj021695: to=<******>,
ctladdr=<xxxx at amnesiac.xxxx> (80/80), delay=1+18:01:02,
xdelay=00:00:14, mailer=esmtp, pri=8221553,
relay=mail2.ukrhosting.com. [91.196.0.5], dsn=4.3.0, stat=Deferred:
451 DNS temporary failure (#4.3.0)


I've disabled the firewall, I have a known working named on localhost,
and resolv.conf is pointing to localhost. Any ideas?