display_sub_nav = function(el) {
	new Ajax.Updater('work-navigation', Event.element(el).href, {
		parameters: { ajax: true },
		insertion: Insertion.After,
		onCreate: function() { 
			if ($('work-sub-navigation')) {
				$('work-sub-navigation').remove();
			}
	 	}
	});
	
	Event.stop(el);
}

Event.observe( window, 'load', function() {
	$$("#work-navigation a").invoke( 'observe', 'click', display_sub_nav );
});