Setting RadioButtonGroup property selectedValue to null

Steps to reproduce:

Create a set of spark RadioButtons associated with a spark RadioButtonGroup.

Bind the selectedValue property of the RadioButtonGroup to a variable.

Assign the value of one of the RadioButtons to the variable.

Assign null to the variable.

Actual Results:

Changing the variable to the value of the one of the RadioButtons changes the selectedValue and selection properties of the RadioButtonGroup.

Changing the variable to null changes the selectedValue property but not the selection property.

The selectionValue is null but one of the RadioButtons is still selected.

Expected Results:

Changing the selectedValue to null should set the selection property to null as well.

Workaround (if any):

Using selection instead of selectedValue.

Notes:

This is inconsistent behavior. Either the selectedValue should not change the selection or it should implement the ability to deselect all RadioButtons by setting it to null.

If the latter was implemented, it would enable a presentation pattern design to control the RadioButtonGroup with a single property through selectedValue rather than selection (so that the controller does not need to know about the RadioButton objects).