Also use the real backgroundcolor - which unfurtunately makes the
button look bad because the bg is almost white - more tweaking needed.
svn path=/trunk/KDE/kdebase/workspace/; revision=694578
get rid of xrender stuff
did this to get smooth painting:
widget()->setAttribute( Qt::WA_PaintOnScreen, false);
svn path=/trunk/KDE/kdebase/workspace/; revision=688425