如何避免『單線程』砍站!?

如標題, 我公司的網站一直被一個神經病砍, 而且不是用『多線程』, 而是單線程...

現在我很困擾的是不知道該用什麼方法去阻攔他, 我會用簡單的 iptables , 但是只能
阻擋單個ip 或一個網段, 現在ADSL這麼發達, 他一直換ip我也不勝其擾...

請大家教一下該如何防治, 謝謝!!

ps. 附上一段 Nginx Log 供大家參考:

[root@centos /etc]# cat /var/log/nginx/access.log |grep 125.230.70.167

125.230.70.167 - - [21/May/2013:15:06:39 +0800] "GET /10000 HTTP/1.1" 302 2046 "-" "Mozil
la/5.0 (compatible; MSIE 9.0; Windows NT 6.1; WOW64; Trident/5.0; BOIE9;ZHTW)"
125.230.70.167 - - [21/May/2013:15:06:41 +0800] "GET /10001 HTTP/1.1" 200 36631 "-" "Mozi
lla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; WOW64; Trident/5.0; BOIE9;ZHTW)"
125.230.70.167 - - [21/May/2013:15:06:43 +0800] "GET /10002 HTTP/1.1" 302 2046 "-" "Mozil
la/5.0 (compatible; MSIE 9.0; Windows NT 6.1; WOW64; Trident/5.0; BOIE9;ZHTW)"
125.230.70.167 - - [21/May/2013:15:06:44 +0800] "GET /10003 HTTP/1.1" 302 2046 "-" "Mozil
la/5.0 (compatible; MSIE 9.0; Windows NT 6.1; WOW64; Trident/5.0; BOIE9;ZHTW)"
125.230.70.167 - - [21/May/2013:15:06:45 +0800] "GET /10004 HTTP/1.1" 302 2046 "-" "Mozil
la/5.0 (compatible; MSIE 9.0; Windows NT 6.1; WOW64; Trident/5.0; BOIE9;ZHTW)"
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