now this seems to be much easier,
just wanna share this with you.
now realmlist.wtf has been removed from the client,
waht now to do is:
open your config.wtf file in your WTF folder,(open with notepad)
find(ctrl+f) if there's a line like
set portal 'us', change 'us' into 'cn'. done.
if there's not a portal set,just copy and paste it to the end.
start with wow.exe or launcher.exe
SET locale "enUS" this makes your client an english version.
SET portal "cn" this means you will login CN server.