I recently upgraded to the new KDE in testing (from 3.5.3-1 to 4:3.5.4-2). After this, subpixel rendering did not work anymore, although it was still shown as selected in the font configuration dialog. To fix it, I had to turn off subpixel rendering, apply the change, and then turn it back on again. It seems to work correctly after this. This should perhaps be documented somewhere, if it isn't already. Marcus