Chinese-simple translation

hi, all
I have translated this module in chinese-simple, see the attachments plz. (utf-8 format)
If you can add this in next version that will be great.
Strange is, when i put this files named with username_check.zh-hans.po or zh-hans.po, i can not see the right translation when i load the page in zh-hans language. have i missed some configuration?
best regard