Event.observe(window, 'load', function ()
{
	var nodes = document.getElementById('nav').getElementsByTagName('TD');
	var nodes_quant = nodes.length;
	for ( var i = 0 ; i < nodes_quant ; ++i ) {
		nodes[i].onmouseover = function(){
			this.className += ' hover';
		}
		nodes[i].onmouseout = function(){
			this.className = this.className.replace(new RegExp(" ?hover\\b"), "");
		}
	}
}
);