addLoadEvent(setUpLinks);
	
	function setUpLinks()
	{
		var nav= $('nav');
		var links = $$('nav', 'A');
		
		for(var i = 0; i < links.length; i++)
		{
			addEvent(links[i], 'click', stopDefault);
			addEvent(links[i], 'click', loadContent);
		}
	}

	function loadContent(evt)
	
	{
		if(evt)
		{
			var target = evt.target;
		}
		else
		{
			var target = window.event.target;
		}
		
		var url=target.getAttribute('href');
		getExternalContent(url,'placeholder',true);
	}