How can i make a QProgreessBar with rounded edges and gradient color background green-yellow-orange-red? ( I'm using QT4.3 embedded linux )

I'm trying with stylesheet. Gradient works perfectly, but rounded edges no.

the code is this:

bar.setStyleSheet( "QProgressBar::chunk:vertical { background: QLinearGradient(x1: 0.5, y1: 1, x2: 0.5, y2: 0, stop: 0 #4bfd05, stop: 0.35 #fdee05, stop: 0.75 #fd9d05, stop: 1 #fd051c); border: 1px transparent; border-radius: 8px; color: transparent}");


what's wrong??


Thanks