window.addEvent('domready', function() {
    var myTips = new Tips($$('.tipz'), {className: 'tooltip',
      initialize: function(){ this.tip.setStyle('opacity', 0 ); },
      onShow: function () { this.tip.fade('in'); },
      onHide: function() { this.tip.setStyle('opacity', 0 ); }
    });
  });