【急急难难】/var/log/wtmp文件显示问题，高手请进！

[root@xx-LOG01 ~]# uname -a
Linux xx-LOG01 2.6.18-194.el5PAE #1 SMP Tue Mar 16 22:00:21 EDT 2010 i686 i686 i386 GNU/Linux
[root@xx-LOG01 ~]# who /var/log/wtmp |grep "cq_hugx"
cq_hugx pts/2 2013-08-20 14:22 (10.190.192.200)
cq_hugx pts/2 2013-08-20 16:51 (10.190.192.200)
cq_hugx pts/2 2013-08-23 13:24 (10.190.192.247)
cq_hugx pts/2 2013-08-30 14:22 (www.cq.10086.cn)
cq_hugx pts/2 2013-08-30 16:57 (www.cq.10086.cn)
cq_hugx pts/2 2013-09-04 17:46 (www.cq.10086.cn)
cq_hugx pts/2 2013-09-05 09:05 (www.cq.10086.cn)
cq_hugx pts/2 2013-09-06 10:38 (www.cq.10086.cn)
cq_hugx pts/2 2013-09-09 09:24 (10.190.192.247)
cq_hugx pts/2 2013-09-11 18:05 (www.cq.10086.cn)
cq_hugx pts/2 2013-09-13 17:45 (www.cq.10086.cn)
cq_hugx pts/2 2013-09-22 11:26 (10.190.192.247)
cq_hugx pts/2 2013-09-25 14:53 (www.cq.10086.cn)
cq_hugx pts/2 2013-09-26 17:46 (www.cq.10086.cn)

第四列源地址列既然显示的是域名，奇怪了，之前从来没发生这种情况，请大神帮忙解答，如何才能显示出ip地址，谢谢！
ps：我登陆设备的网络是移动的。