Event.observe(window, 'load', function(){
    $$('tbody tr.tablehighlight').each(function(element){
        Event.observe(element, 'mouseover', function(event){
            var el = Event.element(event);
            if(el.nodeName != 'tr') {
            	el = el.up('tr');
            }
            el.addClassName('highlight');
        })
        Event.observe(element, 'mouseout', function(event){
            var el = Event.element(event);
            if(el.nodeName != 'tr') {
                el = el.up('tr');
            }
            el.removeClassName('highlight');
        })
    });
});