function doNavRollovers() {
	
	var $nav = $("mainnav");
	
	var $buttons = $nav.childElements();
	
	$buttons.each(function($link) {
		var $img = $link.firstDescendant();
		$img.up = $img.src;
		var $src_split = $img.src.split("/");
		var $file = $src_split.pop();
		var $filesplit = $file.split("_");
		var $filesplit2 = $filesplit.pop().split(".");
		var $overfile = "template/"+$src_split[4]+"/"+$src_split[5]+"/"+$filesplit[0]+"_"+$filesplit[1]+"_"+"over"+".png";		
		$img.over = $overfile;		
		Event.observe($img,"mouseover",doImgOver.bindAsEventListener($img));
		Event.observe($img,"mouseout",doImgOut.bindAsEventListener($img));
		
	})
	
}

function doImgOver() {
	this.src = this.over;
}

function doImgOut() {
	this.src = this.up;
}