[gloomyBrain]

Правильнее будет как-то так

package {
 
	import flash.display.Sprite;
	import flash.events.Event;
 
	/**
	 * ...
	 * @author gloomyBrain
	 * @mail CartoonRaccoon@gmail.com
	 */
 
	public class Main extends Sprite {
 
		public function Main():void {
			if (this.stage) init();
			else this.addEventListener(Event.ADDED_TO_STAGE, init);
		}
 
		private function init(evt:Event = null):void {
			this.removeEventListener(Event.ADDED_TO_STAGE, init);
 
			// entry point
 
			var myFirstSprite:Sprite = new Sprite();
			myFirstSprite.alpha = 0.5;
 
			var mySecondSprite:Sprite = new Sprite();
 
			var myContainer:Sprite = new Sprite();
 
			myContainer.addChild(myFirstSprite);
			myContainer.addChild(mySecondSprite);
 
			this.addChild(myContainer);
 
		}
 
	}
 
}