CB

When calling getAuthorisedViewLevelsIds it only every returns 0 on J1.5. This appears due to aid in the Joomla user object always being null. This should not be the case however as it should contain the top most access level of the user.

Current usage (which is correct):
$user =& JFactory::getUser( (int) $user_id );
$level = $user->get( 'aid', 0 );

This appears to be an issue with Joomla it self and perhaps a different method needs to be used to retrieve the users view access level.