[iNils]

Лучше так

var arrayMC:Array = [];
for (var i:Number = 0; i < 3; i++) {
	var mc:MovieClip = _root.createEmptyMovieClip ('maski' + i, _root.getNextHighestDepth ());
	arrayMC.push (mc);
	mc.array = [];
	for (var j:Number = 0; j < 22; j++) {
		var sub:MovieClip = mc.attachMovie ('maska' + i, 'maska' + j, mc.getNextHighestDepth (), {_x:j * 15});
		mc.array.push (sub);
	}
}
function playagain () {
	var len:Number = arrayMC.length;
	for (var i:Number = 0; i < len; i++) {
		var mc:MovieClip = arrayMC[i];
		var lenSub:Number = mc.array.length;
		for (var j:Number = 0; j < lenSub; j++) {
			mc.array[j].play ();
		}
	}
}
myI = setInterval (playagain, 3000);