Programmatically deselecting a FxRadioButton doesn't clear selectedValue of FxRadioButtonGroup

Steps to reproduce:
1. Compile & run:
<?xml version="1.0" encoding="utf-8"?>
<FxApplication
xmlns="http://ns.adobe.com/mxml/2009" xmlns:local="*"
backgroundColor="0xFFFFFF" >
<layout><VerticalLayout/></layout>

<Declarations>
<FxRadioButtonGroup id="srg"/>
</Declarations>

<FxRadioButton id="s1" label="Spark 1" groupName="srg"/>
<FxRadioButton id="s2" label="Spark 2" groupName="srg"/>
<FxRadioButton id="s3" label="Spark 3" groupName="srg"/>
<FxRadioButton id="s4" label="Spark 4" groupName="srg"/>
<FxRadioButton id="s5" label="Spark 5" groupName="srg"/>

<FxButton label="deselect programmatically" click="srg.selection.selected=false"/>
<FxButton id="btn" label="Get selectedValue" click="lbl.text=srg.selectedValue.toString()"/>
<FxButton label="move groups" click="srg.selection.groupName='nothere'"/>

<Label id="lbl" />
</FxApplication>

2. Select any FxRadioButton
3. Click the "deselect programmatically" button
4. Click the "Get selectedValue" button

Actual Results:
selectedValue returns the label of the last selected FxRadioButton

Expected Results:
selectedValue should return null since the FxRadioButton is no longer selected

Workaround (if any):