linux firefox display chinese font

"ssh -X root@cent5a" found firefox can not display chinese. The correct procedure is:
(1) #locale;  shows current display
(2)#locale -a ; find the chinese setting: zh_CN.gb2312
(3)change /etc/sysconfig/i18n from:
                LANG="en_US.UTF-8"
                SYSFONT="latarcyrheb-sun16"
    to:
                LANG="zh_CN.gb2312"
                SYSFONT="lat0-sun16"
(4) reboot to run "locale" shows:
    LANG="zh_CN.gb2312"
SYSFONT="lat0-sun16"
[root@cent5a sysconfig]# locale
LANG=zh_CN.gb2312
LC_CTYPE="zh_CN.gb2312"
LC_NUMERIC="zh_CN.gb2312"
LC_TIME="zh_CN.gb2312"
LC_COLLATE="zh_CN.gb2312"
LC_MONETARY="zh_CN.gb2312"
LC_MESSAGES="zh_CN.gb2312"
LC_PAPER="zh_CN.gb2312"
LC_NAME="zh_CN.gb2312"
LC_ADDRESS="zh_CN.gb2312"
LC_TELEPHONE="zh_CN.gb2312"
LC_MEASUREMENT="zh_CN.gb2312"
LC_IDENTIFICATION="zh_CN.gb2312"
LC_ALL=
(5) install chinese font:
   yum install fonts-chinese