Elastic Button HELP!

I’m trying to get this button to bounce in and out when rolled over. The script works in one document but I can’t get it to work when I copy it to another. Any advice?

MovieClip.prototype.jumpSkale = function(obj, rush, friction) {
this.tempo += (obj - this._xscale) * rush;
this.tempo *= friction;
this._xscale = this._yscale += this.tempo;
};

for (var i = 1; i <= 3; i++) {
this[“MC” + i].onEnterFrame = function() {
if (this.hitTest(_root._xmouse, _root._ymouse, true)) {
this.jumpSkale(400, .9, .6);
} else {
this.jumpSkale(100, .6, .5);
}
};
this.onEnterFrame = function() {
this._xscale = this._yscale = _root[“MC” + this.nr]._xscale;
};
}