What's wrong with my AS

programming flash
1

Why wont the code, Key.isUp work???

I need it so when the right key is relesed, the timeline goes back to frame 1.

this.onKeyDown = function() {
if (Key.isDown(Key.RIGHT)) {
this.gotoAndPlay(2);
}
if (Key.isUp(Key.RIGHT)) {
this.gotoAndPlay(1);
}
};
this.stop();
Key.addListener(this);

Thanks!!!