root 에 이런메세지가 계속 쌓이네요

/var/spool/mail 안에 root에 이런 메세지가 계속 옵니당 으케된거죠????

From MAILER-DAEMON@ns.oooooo.co.kr  Wed Jun 12 08:21:53 2002
Date: Wed, 12 Jun 2002 08:21:53 +0900
From: Mail Delivery Subsystem <MAILER-DAEMON@ns.oooooo.co.kr>
To: postmaster@ns.oooooo.co.kr
MIME-Version: 1.0
Content-Type: multipart/report; report-type=delivery-status;
        boundary="VFU24004.1023837713/ns.yuyang.co.kr"
Subject: Postmaster notify: User unknown
Auto-Submitted: auto-generated (postmaster-notification)

This is a MIME-encapsulated message

--VFU24004.1023837713/ns.yuyang.co.kr

The original message was received at Wed, 12 Jun 2002 08:21:32 +0900
from localhost

   ----- The following addresses had permanent fatal errors -----
<tjk@net.zt.ua>

   ----- Transcript of session follows -----
... while talking to mail.net.zt.ua.:
>>> RCPT To:<tjk@net.zt.ua>
<<< 550 5.1.1 <tjk@net.zt.ua>... User unknown
550 <tjk@net.zt.ua>... User unknown

--VFU24004.1023837713/ns.oooooo.co.kr
Content-Type: message/delivery-status

Reporting-MTA: dns; ns.oooooo.co.kr
Arrival-Date: Wed, 12 Jun 2002 08:21:32 +0900

Final-Recipient: RFC822; tjk@net.zt.ua
Action: failed
Status: 5.1.1
Remote-MTA: DNS; mail.net.zt.ua
Diagnostic-Code: SMTP; 550 5.1.1 <tjk@net.zt.ua>... User unknown
Last-Attempt-Date: Wed, 12 Jun 2002 08:21:51 +0900

도데체 먼말인지?? 제가 생각하기에는 그쪽서버에서

거부하는거 같은데 맞져?? 근디 누군가 계속 보내는거죠??

우리가 중계기 역할을 하던데 막는 방법은 뾰족히 없죠??

미노님이 조언좀 부탁요~

대한민국~ 빠밤밤밤빠~