[flexcoders] Can't get focusRoundedCorners to work on ButtonBar

[Patrick Mineault]

I'm trying to accomplish the following: have a ButtonBar in which each
of the buttons has rounded corners (unlike the default where only the
left most and right most buttons have some rounded corners). I've been
playing with this for a while now, and I can't get it to work. Here's
some minimal code:

<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml";
    xmlns="*" 
    layout="vertical">
    <mx:Style>
        ButtonBarButton
        {
                focus-rounded-corners:"tl tr bl br";
                corner-radius:10;
        }
        .ButtonBarButton
        {
                focus-rounded-corners:"tl tr bl br";
                corner-radius:10;
        }
    </mx:Style>
    <mx:ButtonBar 
            focusRoundedCorners="tl tr bl br"
            dataProvider="{vs}" 
            firstButtonStyleName="ButtonBarButton"
            buttonStyleName="ButtonBarButton"
            lastButtonStyleName="ButtonBarButton"
    />
    <mx:ViewStack 
        id="vs" >
        <mx:Box label="1">
                <mx:Button label="button 1" />
        </mx:Box>
        <mx:Box label="2">
                <mx:Button label="button 2" />
        </mx:Box>
        <mx:Box label="3">
                <mx:Button label="button 3" />
        </mx:Box>
    </mx:ViewStack>
</mx:Application>

As you can corner-radius works correctly but focusRoundedCorners fails
in all circumstances. Some of the code here is redundant or
non-sensical but it's just to show that I have tried everything I
could think of. Any ideas?