Why can not draw Chinese string on pixbap?

["chen.shengqi" <chen shengqi connet com tw>]

Dear sir:
    I'm using gnome 2.0 on solaris 8 for x86, the gnome system can show Chinese menu ok, but in my 
application, I use gdk_draw_text can not draw out chinese string(in GB2312), if I use gdk_mbstowcs convert it 
to wchar and use gdk_draw_text_wc to draw it, it still failed,just show some unkown characters. How to draw 
it ?
    thanks.