Bug with DB_NestedSet's HTML_Menu-Output?

Hi all I'm having a problem with DB_NestedSet's Menu-Output... TreeMenu-Output works fine, I get 4 items, all in the right position. But with the Menu-Output I get 5 items, one is printed out twice, in the wrong location. this is the data: <snip> Array (

    [1] => Array
        (
            [id] => 1
            [rootid] => 1
            [l] => 1
            [r] => 6
            [norder] => 1
            [level] => 1
            [name] => menu1
            [link] =>
        )

    [4] => Array
        (
            [id] => 4
            [rootid] => 4
            [l] => 7
            [r] => 8
            [norder] => 1
            [level] => 1
            [name] => menu2
            [link] =>
        )

    [2] => Array
        (
            [id] => 2
            [rootid] => 1
            [l] => 2
            [r] => 3
            [norder] => 1
            [level] => 2
            [name] => menu_2_de
            [link] => index.php?page=&menu_id=2&lang=de
        )

    [3] => Array
        (
            [id] => 3
            [rootid] => 1
            [l] => 4
            [r] => 5
            [norder] => 2
            [level] => 2
            [name] => menu_3_de
            [link] => index.php?page=&menu_id=3&lang=de
        )

) </snip> this is the Menu-Output: <snip> menu1 menu_2_de menu_3_de menu_3_de menu2 </snip> as you can see menu_3_de is there twice, and one instance of it is even on the wrong level... Can someone tell me where my mistake is? Stephan