Is dhtmlxGird’s title cant not use Traditional Chinese?
Actually component is encoding agnostic, it can work with any encoding which supported by browser.
The only requirement for non-utf encoding - it must be clearly specified in used XML header
<?xml version="1.0" encoding="___HERE___" ?>
If XML and page have necessary encoding the grid will render data correctly.
Also, there may be some issue with special chars in XML ( there was problem reported with Chinese ) , so if data still not loaded - please try to include it in CDATA sections