I've created a role:
$role = add_role( 'role', 'role', array('read' => true) );
and so created a cap:
$role->add_cap( 'cap' );
after this I'd created a submenu in admin menu with 'cap' as capability argument. So the problem is that the user with 'role' role can see the submenu but the site admin can't see the submenu, so the question is: I have to add 'cap' to admin role ? isn't it automatically ?