$(document).ready(function() {
$("#subnav div.sidebar-with-title").hide();
$("#subnav div.sidebar-with-title.current").show();
$("ul#nav li span").addClass("link");
$("ul#nav li span").click(function() {
var id = (this.id);
$("#subnav div.sidebar-with-title").hide();
$("#subnav div.sidebar-with-title#"+id+"_menu").show();
});
});