can an actionscript member listen the possess propertychange events?

i have circlebutton category actionscript.
i wish know someone presumably altered 'on' property.
i try listening 'onchange' nonetheless never hits eventuality handler.

i know i 'on' ability get/setter nonetheless i probity only controlling [bindable]

can an vigilant listen the possess events?

public category circlebutton extends uicomponent

{
    [bindable]
    open var on:boolean;

    open duty circlebutton()
    {
        this.width = 20;
        this.height = 20;

        graphics.beginfill(0xff6600, 1);
        graphics.drawcircle(width/2, height/2, width/2);
        graphics.endfill();

        this.addeventlistener(mouseevent.roll_over, rollover);  
        this.addeventlistener(mouseevent.roll_out, rollout);        

        this.addeventlistener('onchange', ononchange);
    }       

    private duty ononchange(event:propertychangeevent):void {