On main timeline...
Code:
var isOver = false;
On clips...
Code:
onClipEvent (load) {
	y = 0;
	speedR = 5;
	radius = 100;
	xcenter = 393 / 2;
	ycenter = 325 / 2;
	zcenter = 100;
	angle = 0;
	fl = 150;
	this.onRollOver = function() {
		_root.isOver = true;
	};
	this.onRollOut = function() {
		_root.isOver = false;
	};
}
onClipEvent (enterFrame) {
	_x = Math.cos(angle * Math.PI / 180) * radius + xcenter;
	_y = y + ycenter;
	z = Math.sin(angle * Math.PI / 180) * radius + zcenter;
	scale = fl / (fl + z);
	_xscale = _yscale = scale * 100;
	angle += ((_root.isOver) ? 0.5 : speedR);
	if (angle > 359) {
		angle -= 360;
	}
}