일단 에러 메시지입니다.
 From web  Fri Nov 16 11:33:53 2001
Date: Fri, 16 Nov 2001 11:33:53 +0900
From: Mail Delivery Subsystem <MAILER-DAEMON@localhost>
To: web@localhost MIME-Version:1.0
Content-Type: multipart/report; report-type=delivery-status;
        boundary="LAA16822.1005878033/localhost"
Subject: Returned mail: Data format error
Auto-Submitted: auto-generated (failure)
 This is a MIME-encapsulated message
 --LAA16822.1005878033/localhost
 The original message was received at Fri, 16 Nov 2001 11:33:47 +0900
from web@localhost     ----- The following addresses had permanent fatal errors -----
han2-00-2 at hanmail.net     ----- Transcript of session follows -----
... while talking to mx5.hanmail.net.:
>>> MAIL From:<web@localhost> SIZE=50
<<< 553 5.5.4 <web@localhost>... Domain name required
501 han2-00-2 at hanmail.net... Data format error
 --LAA16822.1005878033/localhost
Content-Type: message/delivery-status
 Reporting-MTA: dns; localhost
Arrival-Date: Fri, 16 Nov 2001 11:33:47 +0900
 Final-Recipient: RFC822; han2-00-2 at hanmail.net Action: failed
Status: 5.1.3
Remote-MTA: DNS; mx5.hanmail.net
Diagnostic-Code: SMTP; 553 5.5.4 <web@localhost>... Domain name required
Last-Attempt-Date: Fri, 16 Nov 2001 11:33:53 +0900
 --LAA16822.1005878033/localhost
Content-Type: message/rfc822
 Return-Path:<web>
Received:(from web@localhost)
        by localhost (8.9.3/8.9.3) id LAA16820
        for han2-00-2 at hanmail.net; Fri, 16 Nov 2001 11:33:47 +0900
Date: Fri, 16 Nov 2001 11:33:47 +0900
From: web
Message-Id:<200111160233.LAA16820@localhost>
To: han2-00-2 at hanmail.net Subject: hihihi
 hohoho
 --LAA16822.1005878033/localhost--
 이런 에러가 왜 나지요? 저는 단순희 고정IP할당받은 서버에서 메일만 보내는데 사용하거
든요. 메일 보낼때 sendmail -vt나 mail -s han2-00-2 at hanmail.net 사용하는데 바로 리턴되네요. hosts,res
olv.conf,local-host-names,sendmail.cf,network,ifcfg-eth0등등 파일 다 잘 설정된것 같은데... 어떻게 대처
해야 되나요? 메일서버를 만들어서 dns에 등록까지 해야 제대로 갈까요?  죄송하지만 질문
하나더요. cf/cf디렉토리에 cf랑 mc파일이 많던데... 사용법좀 가르쳐주세요. 고수님들 부탁
합니다.!!!!--han---