В AS 3.0 нехватает типов событий.

[CrazyFlasher]

package {
	import flash.display.DisplayObject;
	import flash.events.Event;
 
	/**
	 * ...
	 * @author Anton Nefjodov
	 */
	public class CommonDisplayObject extends DisplayObject {
 
		public function CommonDisplayObject() {
			super()
		}
 
		override public function set x(value:Number):void {
			super.x = value;
 
			dispatchEvent(new Event("move"));
		}
 
		override public function set y(value:Number):void {
			super.y = value;
 
			dispatchEvent(new Event("move"));
		}
 
		override public function set z(value:Number):void {
			super.z = value;
 
			dispatchEvent(new Event("move"));
		}
	}
 
}