Problem with streamless scrolling

1

Hi, I having problem with this follow streamless scrolling.

Please download the file here
http://www.dreamance.com/download/problem.zip

Here is the core code


onClipEvent (load) {
	rowWidth = 0;
	speed = 0.2;
	newPos = this._x;
}
//
//
onClipEvent (enterFrame) {
	_x = _x+Math.ceil((newPos-_x)*speed);
	//
	trace("x "+_x);
	trace("n "+newPos);
	if (_x<((rowWidth/3)*-1)-3) {
		_x = 15;
	}
}

Basically, when user click on the right button, the movie will scroll (working) When it _x exceed it width, it will reposition itself to create a streamless illusion (not working) Can someone please enlighten me what went wrong?