How to insert a dynamic menu item for a node by hook_menu?

Probably it’s a simple problem – but though I searched in the forums for hours I didn’t find a solution that works for me. So I ask for help:

I want to build a dynamic menu in Drupal 5 in which I want to display menu items for some particular nodes (witch I calculate depending on the taxonomy system).

In my module I tried to insert a menu item with:

  $items[] = array(
    'path'                => 'node/15',
    'title'               => $title,
    'type'                => MENU_NORMAL_ITEM,
    'access'              => TRUE
  );

But this menu item isn’t shown in any menu! And even if it would be shown I am not able to determine where (in which menu and at which position) it would be shown, because this is determined by the ‘path’, which is 'node/15' instead of 'navigation/itemname'.

So I tried to do it with:

  $items[] = array(
    'path'                => 'navigation/itemname',
    'title'               => $title,
    'callback'            => 'drupal_goto',
    'callback arguments'  => array('node/15'),
    'type'                => MENU_NORMAL_ITEM,
    'access'              => TRUE
  );

Now the menu item is shown in the menu ‘navigation’ and if I click on this menu item the right node is called. But this is true only if the menu item is at the first level. If it is deeper in hierarchy the menu does not open and the menu item isn’t shown as active. Well I think, this might be ok, because the node which is shown is 'node/15' while the menu path is 'navigation/itemname'. So there is no reason to activate the menu.

So I tried to tell Drupal that 'navigation/itemname' is the active item by adding to the hook_nodeapi:

case 'view':
   menu_set_active_item('navigation/itemname');
   break;

Result: The menu opens and the menu item is active. But now Drupal does not know any more that the shown node is 'node/15' and so the tabs ‘view’ and ‘edit’ aren’t shown any more.

Well, now I am at my wits’ end and hoping someone can tell me what I’m doing wrong. Many thanks in advance!