How to cause a node of a particular type to appear in a menu tree?

Hi,
I've searched all over, and tried code snippets etc., but I just cannot get this to work!

I have just added a FAQ section to the company website (running drupal 5.2 at www.rapitasystems.com). I have created a 'content type' (FAQ entry) which contains each FAQ. I have written a PHP page (/faqlist) which allows FAQs to be shown as a list (either all, or a particular section). This FAQ page has a left-menu entry, which is fine and works as required.

Now, the tricky bit :-) When someone clicks on *any* FAQ, I would like the left-menu to remain expanded at 'FAQ'. I have managed to get the breadcrumb sorted out (by writing a template: node-faq-tpl.php) but although the documentation I have read implies that the menu entry should be updated, this does not seem to be the case!

The code that I have to create the breadcrumb (in the template file) is as follows:

<?php
 $node->breadcrumb[] = array('path' => 'prodserv', 'title' => t('Products and Services'));
 $node->breadcrumb[] = array('path' => 'rapitime', 'title' => t('RapiTime'));
 $node->breadcrumb[] = array('path' => 'faqlist','title' => t('FAQ'));
 $node->breadcrumb[] = array('path' => $node_url,'title' => t('X'));
 if ($page) {
   menu_set_location($node->breadcrumb);
 }
?>

but the menu is not set, even though the path appears to be correct! (Incidentally, the 'X' entry into the breadcrumb trail is simply there to ensure that the FAQ part of the breadcrumb displays...)

Does this function not work in a template? Should I take a different approach? Do I need to write a simple 'faq' module to perform this?

As you can tell, I am a little lost :-)

Thanks