Moderator Group Posting Fail

[w2kjun at corp.thrunet.com]

I can't post articles to Moderator Group .
In mailbox of admin, there is error messages like this...


   ----- The following addresses had permanent fatal errors -----
fr-comp-os-linux-configuration at moderators.isc.org

   ----- Transcript of session follows -----
550 fr-comp-os-linux-configuration at moderators.isc.org... Host unknown (Name
server: mailhost.: host not found)

--NAA27268.985840350/nntpko
Content-Type: message/delivery-status

Reporting-MTA: dns; nntpko
Arrival-Date: Thu, 29 Mar 2001 13:32:29 +0900 (KST)

Final-Recipient: RFC822; fr-comp-os-linux-configuration at moderators.isc.org
Action: failed
Status: 5.1.2
Remote-MTA: DNS; mailhost
Last-Attempt-Date: Thu, 29 Mar 2001 13:32:30 +0900 (KST)

--NAA27268.985840350/nntpko
Content-Type: message/rfc822

Return-Path: <news>
Received: (from news at localhost)
        by nntpko (8.8.8+Sun/8.8.8) id NAA27235
        for fr-comp-os-linux-configuration at moderators.isc.org; Thu, 29 Mar
2001 13:32:29 +0900 (KST)
To: fr-comp-os-linux-configuration at moderators.isc.org
Path: not-for-mail
From: "yoon" <w2kjun at korea.com>
Newsgroups: fr.comp.os.linux.configuration
Subject: What is linux??
Date: Thu, 29 Mar 2001 13:35:15 +0900
Organization: korea usenet service
Lines: 3
Message-ID: <99udr1$qj0$1 at nntpko.korea.com>
NNTP-Posting-Host: 210.117.24.33
X-Trace: nntpko.korea.com 985840289 27232 210.117.24.33 (29 Mar 2001
04:31:29 GMT)
X-Complaints-To: usenet at newsgroup.korea.com
NNTP-Posting-Date: 29 Mar 2001 04:31:29 GMT
X-Priority: 3
X-MSMail-Priority: Normal
X-Newsreader: Microsoft Outlook Express 5.50.4133.2400
X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4133.2400

Help me


I checked /etc/mail/sendmail.cf ...    
 in that file, there is a like this...

# "Smart" relay host (may be null)
DSmailhost.$m

So, I just wanna know Whether this line is related with not posting
Moderator group..??

What shall i do to post to moderator??

Ple help me...