I'm building a PHP site using tabs to re-query the database for different criteria. My problem is that even if the target ajax file contains <?php>echo "testing";<?>, the tab just displays the "loading" message. I noticed this also happens on the http://ui.jquery.com/demos/tabs#ajax page but not when you click on the http://ui.jquery.com/applications/demos/tabs/ajax.html link. Any clues?