I'm developing a theme based on Drupal 5.0 RC1. In my menu structure, I have primary and secondary links. The secondary links menu has some nested links. However, with the snippet which is provided in the documentation, these nested links are never displayed! I have this snippet in my page.tpl.php:

<?php print theme('links', $secondary_links, array('class' => 'nav')) ?>

Is there any way I can get my secondary links to display the nested links if I click on a parent item? Thanks!