owh that is weired...
this is the first time to come across such a weired problem...
why the chiness have to be discluded from that?
usually every single person in the glob has the right to do whatever he or she wants as long as his or her deeds are legal...
so, why dont your users check their registered name and passwords as they might have used chiness letters instead of English letters when they done the registration...
or try to contact them to learn more about the difficulty in accessing themselves into your site...
smiley...
Beauty
lifeishope23