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);
}

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);
}

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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