Problem with RadioGroup / Ajax

Hi,
I'm having an issue with a RadioGroup that is used in conjunction with a ListView, the populateItem method for the ListView looks like:

public void populateItem(final ListItem listItem) {
final PoDetailAdj pda = (PoDetailAdj) listItem.getModelObject();

      listItem.add(new Radio("radio-status-pending", new Model()));
listItem.add(new Radio("radio-status-approved", new Model()));
}

The RadioGroup encloses the entire ListView, and the RadioGroup is added to a form on the page. The display works fine, so I added AjaxFormChoiceComponentUpdatingBehavior to the RadioGroup, but changing the Radio values doesn't trigger the onUpdate method of the RadioGroup. I also tried having one RadioGroup per ListItem (a new RadioGroup defined for every row) but that didn't work either. I'm starting to think that maybe the ListView is the problem. Any thoughts or suggestions?

Travis Boswell