Actionscript3. Прозрачность TextField

var mySprite:Sprite = new Sprite();
mySprite.blendMode = BlendMode.LAYER;
addChild(mySprite);

var myText:TextField = new TextField();
mySprite.text = "Some text";
mySprite.addChild(myText);

mySprite.alpha = 0.5;  //Прозрачность 50%