Hmmmm................ something new........
Well, to err on the safe side, suggest that you should bring in your Nokia 6600 to the Nokia service Centre and see what they can do about it, rather than trying otherwise.
6600 is using the sybrian os. hence chinese isn't available.
till date nokia has still yet to solve this problem. hence, no chinese for the time being even at nokia service centre, they cant do anything.