Now Qt4 applications' all characters show twisted with WenQuanYi ZengHei or Bitmap font. Change the font with Qt4 Setting to Bitstream Character or WenQuanYi Mono font in order to show letters regularly.
scim-im.org's method: create 75scim file under /etc/X11/Xsession.d/ with following lines (if you have 90im-switch, better to remove it for this setup):