wp_list_categories selected states only working 2 levels down

Hi all,

I’m playing around with the navigation with wordpress and it has really improved with 2.7. I basically have a single line of code to list all categories and their siblings in correctly formatted lists. Here is the line of code:

<?php wp_list_categories('show_count=0&amp;title_li=0');

The only issue, is the selected classes. There only seems to be 2 levels of classes – current-cat-parent & current-cat, which means when I am down to the third level of the category hierarchy, the parent tab no longer has a class to show it is selected. Here is the HTML it is producing:

<ul id="topNavigation">
	<li class="cat-item cat-item-1">
		<a href="/">Main Parent</a>
		<ul class="children">
			<li class="cat-item cat-item-7 current-cat-parent">
				<a href="/">test category</a>
				<ul class="children">
					<li class="cat-item cat-item-8 current-cat"></li>
				</ul>
			</li>
		</ul>
	</li>
</ul>

I would like the parent category to be selected for all levels of sub-nagation. Is it possible to do this? I’ve been searching to no avail for ages and would greatly appreciate any help.

Thanks