transparent alpha pixmap qpushbutton/qlabel with qt 3.x embedded linux

Hello!
I'm more than fresh to qt!. my third day!;-)

i'm bounded to qt 3.8x embedded linux and to the designer and want to use button's/label where you just see the loaded pixmap with transparency.

altough no (big) problem under qt 4.x where i change the stylesheet to alpha=0 for disabling drawing ( i hope the widget knows it can't be visible with 0 alpha and doesn't go all the way down the rendering pipeline;-)
for qt 3.x the underlaying button/label/widget is always drawing.

i need full ( 8 bit ) alpha visually and don't want to use 1 bit region masks like in the tux example.

can someone please point me to an example how i can disable the normal button painting and draw just a 32 bit pixmap under qt 3.x?
or do custum widget's exist?
or is it just not possible with qt 3.x?

if overloading is necessary can i still define the layout in the designer?
( i can't change to much existing code. at least none...)

Thanks for helping me solving this. i just can't find example code for qt3.x!
smile!;-)