2차도메인 문제입니다.

안녕하세요.
다름이 아니구요.
제가 지금 레드헷 9.0 을 쓰고있습니다.
근데 2차도메인을 세팅을 했는데요.
[root@www root]# nslookup -sil aaa.bbb.co.kr
Server:         211.xxx.xxx.xxx
Address:        211.xxx.xxx.xxx#53

** server can't find aaa.bbb.co.kr: SERVFAIL
---------수정내용--------
========http.conf============
<VirtualHost 211.xxx.xxx.xxx>
        ServerAdmin aaa@hanmail.net
        DocumentRoot /home/aaa/public_html
        ServerName aaa.bbb.co.kr
</VirtualHost>

=======named.conf===========
zone "aaa.bbb.co.kr" IN {
        type master;
        file "bbb.co.kr";
        allow-update { none; };
};
======bbb.co.kr==========
$TTL 86400
@               IN      SOA     ns.bbb.co.kr. root.bbb.co.kr. (
                                        2003042402      ; Serial
                                        28800           ; Refresh
                                        14400           ; Retry
                                        3600000         ; Expire
                                        86400   )       ; Minimum TTL

                IN      NS      ns.bbb.co.kr.
                IN      A        211.xxx.xxx.xxx
localhost  IN      A       127.0.0.1
ns            IN      A        211.xxx.xxx.xxx
www        IN       A       211.xxx.xxx.xxx
aaa          IN      A        211.xxx.xxx.xxx
============================================
이렇게 세팅을 했습니다...
어떤 문제인지...답변..부탁드리겠습니다.

참고)
[root@www named]# nslookup -sil bbb.co.kr
Server:         211.xxx.xxx.xxx
Address:        211.xxx.xxx.xxx#53

Name:   bbb.co.kr
Address: 211.xxx.xxx.xxx
% 1차도메인은 잘됩니다.