たまに使うのでメモ。

private function ArrayShuffle(arr:Array){
	var l = arr.length;
	var newArr = arr;
	while(l){
		var m = int(Math.random()*l);
		var n = newArr[--l];
		newArr[l] = newArr[m];
		newArr[m] = n;
	}
	return newArr;
}