window.addEvent('domready', function() {
    var preLoadArray = new Array();
    var preLoadNum = 0;
 
    $$('[rollover]').each(function(el){
        var original    = el.src;
        var replacement = el.getAttribute('rollover');
        preLoadArray[preLoadNum] = new Image();
        preLoadArray[preLoadNum].src = replacement;
        preLoadNum++;

        var offsetTop  = 0;
        var offsetLeft = 0;
        offsetTop  = el.getAttribute('offset-top'); 
        offsetLeft = el.getAttribute('offset-left'); 

        el.addEvent('mouseover',function(){
            this.setAttribute('src', replacement );
            if (offsetTop)  { this.setStyle("top",  offsetTop + "px");    }
            if (offsetLeft)  { this.setStyle("left", offsetLeft + "px");  }
        });
 
        el.addEvent('mouseout',function(){
            this.setAttribute('src', original );
            if (offsetTop)  { this.setStyle("top", "0px");     }
            if (offsetLeft)  { this.setStyle("left", "0px");    }
        });
    });
    
    

        
});