New Menu System, 6.2

I am trying to wrap my head around the changes to the new menu system in d6.x and I'm drawing a blank on this one...

I'm looking to do the following:

Item #1
-> Item#2
-> Item #3
-> Item #4
-> etc ...

In drupal 5.x you did this:

  $items[] = array(
    'path' => 'url',
    'title' => t('Url_title'),
    'access' => user_access('access perms'),
    'type' => MENU_ITEM_GROUPING
  );

Now, in 6.x it looks a bit more like this:

$items['url'] = array (
    'title' => 'Url Title',
    'page callback' => 'idkfa_error',
    'access callback' => 'user_access',
    'access arguments' => array('access perms'),
    'type' => MENU_ITEM_GROUPING
  );

So, what I'm having a problem with, MENU_ITEM_GROUPING no longer works... So, how in the bloody hell does one make a nested menu in d6.x?!?