alpha channel problems

[codebehind]

I have a gui that has some qlistwidget with some QStyle.
when i set the alpha channel between 255 and 0 the gui it is not as it is in designer - pictures tells everything.
If i set the alpha channel 0 or 255 it works fine.

QListWidget
{
border-width: 2px;
border-style: solid;
border-color: rgba(0,0,255,255);
border-radius: 5px;
background-color: rgba(165, 165, 165, 200);
selection-background-color: rgba(48, 235, 255, 100);
selection-color: rgb(0, 0, 127);
}

I can not figure out where is the problem. I think the code is compiling with different libraries but i'm not sure. I search everything and everywhere but till now no luck.

I'm working with x11, qt4.6.2
designer.jpg is a cut of what i see while coding - using qtcreator 1.3
app.jpg is what i see when the app runs

[codebehind]

a coorection i'm working with qt 4.6.1

[codebehind]

Finally!
As I thought the problem was with the library. After a long time searching the net I returned to the qt docs. And .... the first thing I read about alpha blending (http://qt.nokia.com/doc/4.6/qcolor.html#alpha-blended-drawing) was

... and on X11 systems that have the X Render extension installed.

believe it or not it was missing :mad: always the same problem .... RTFM!!!!!!

anyway i recompiled the qt framework....

Works great!