document.observe("dom:loaded", function() {
   $$('.tab').invoke("observe", "click", function(tab) {
		var href = tab.element().href;
		new Effect.Fade(replaceme);
		new Effect.Appear('replaceme',
		new Ajax.Updater('replaceme', href, {
		asynchronous: false,
		}));
		tab.stop(); // prevent click from continuing and reloading page
   });
});