import mx.core.UIComponent;
private var newAngle:Number = 0;
private function pushAround( evt:MouseEvent ):void
{
newAngle += 90;
btn2.transformAround( new Vector3D( btn2.width / 2, btn2.height / 2 ), null, null, null,
null, new Vector3D( 0, 0, newAngle ) );
}