[Bgg]

random13, массив выше, а не в самом MovieClip.
Я бы слал событие.

package
{	
	public class MyClass extends MovieClip
	{
	        public static constr PLEASE_TAKE_ME_MY_MASTER:String="please take me my master";
 
	        public function MyClass()
	        {
 	                addEventListener(Event.ADDED_TO_STAGE, init);
	        }
 
	        public function init(obj:Object):void
	        {
                        removeEventListener(Event.ADDED_TO_STAGE, init);
	                dispatchEvent(new Event(PLEASE_TAKE_ME_MY_MASTER, true));
	        }
	}
////////////////////////////////////////////////////////////////////////
	public class Main extends Sprite
	{
	        private var arraySlaves:Array = new Array;
 
	        public function Main()
	        {
 	        	addEventListener(MyClass.PLEASE_TAKE_ME_MY_MASTER, takeHim);
	        }
 
	        public function takeHim(event:Event):void
	        {
	                arraySlaves.push(event.target as MyClass);
	        }
	}
}