[Plugin: PerformerJS] Accordianer doesn’t retract

I want to love this plugin, but so far I have not been able to get any of the functions to work the way I want to, for one reason or another.

The accordianer, for instance, expands properly, but won’t retract. Once a pane is opened, it stays open even when another pane is opened.

I’ve tried this on WP 2.8.6 and 2.9, and it does the same in both. Here is the code I’m using (below).

I’ve tried deactivating all other plugins – that’s not the problem. Any other ideas what could be causing this?

<ul id="navigate">
<li><a class="accordianer group-navigate item-pages" href="#pages">Pages</a>
<div id="pages" class="accordionitem hider" style="list-style-type:none">
[php]wp_list_pages('title_li=');[/php]</div></li>
<li><a class="accordianer group-navigate item-blog" href="#blog">Blog Topics</a>
<div id="blog" class="accordionitem hider" style="list-style-type:none">[php]wp_list_categories('title_li=');[/php]</div></li></ul>

http://wordpress.org/extend/plugins/performerjs/