Сортировка массива

Здравствуйте.

Уже второй день бьюсь над сортировкой массива, никак не могу отсортировать по убыванию

Вообщем, дан массив

Array

(

    [0] => Firefox Setup 9.0.exe

    [1] => Firefox Setup 9.0.1.exe

    [2] => Firefox Setup 8.0.exe

    [3] => Firefox Setup 8.0.1.exe

    [4] => Firefox Setup 7.0.exe

    [5] => Firefox Setup 7.0.1.exe

    [6] => Firefox Setup 6.0.exe

    [7] => Firefox Setup 6.0.2.exe

    [8] => Firefox Setup 6.0.1.exe

    [9] => Firefox Setup 5.0.exe

    [10] => Firefox Setup 5.0.1.exe

    [11] => Firefox Setup 4.0.exe

    [12] => Firefox Setup 4.0.1.exe

    [13] => Firefox Setup 3.6.exe

    [14] => Firefox Setup 3.6.9.exe

    [15] => Firefox Setup 3.6.8.exe

    [16] => Firefox Setup 3.6.7.exe

    [17] => Firefox Setup 3.6.6.exe

    [18] => Firefox Setup 3.6.4.exe

    [19] => Firefox Setup 3.6.3.exe

    [20] => Firefox Setup 3.6.28.exe

    [21] => Firefox Setup 3.6.2.exe

    [22] => Firefox Setup 3.5.exe

    [23] => Firefox Setup 3.5.9.exe

    [24] => Firefox Setup 3.5.8.exe

    [25] => Firefox Setup 3.5.7.exe

    [26] => Firefox Setup 3.5.6.exe

    [27] => Firefox Setup 3.5.5.exe

    [28] => Firefox Setup 3.5.4.exe

    [29] => Firefox Setup 3.5.3.exe

    [30] => Firefox Setup 3.5.2.exe

    [31] => Firefox Setup 3.5.19.exe

    [32] => Firefox Setup 3.5.1.exe

    [33] => Firefox Setup 3.0.exe

    [34] => Firefox Setup 3.0.9.exe

    [35] => Firefox Setup 3.0.8.exe

    [36] => Firefox Setup 3.0.7.exe

    [37] => Firefox Setup 3.0.6.exe

    [38] => Firefox Setup 3.0.5.exe

    [39] => Firefox Setup 3.0.4.exe

    [40] => Firefox Setup 3.0.3.exe

    [41] => Firefox Setup 3.0.2.exe

    [42] => Firefox Setup 3.0.19.exe

    [43] => Firefox Setup 3.0.1.exe

    [44] => Firefox Setup 2.0.exe

    [45] => Firefox Setup 2.0.0.9.exe

    [46] => Firefox Setup 2.0.0.8.exe

    [47] => Firefox Setup 2.0.0.7.exe

    [48] => Firefox Setup 2.0.0.6.exe

    [49] => Firefox Setup 2.0.0.5.exe

    [50] => Firefox Setup 2.0.0.4.exe

    [51] => Firefox Setup 2.0.0.3.exe

    [52] => Firefox Setup 2.0.0.20.exe

    [53] => Firefox Setup 2.0.0.2.exe

    [54] => Firefox Setup 2.0.0.1.exe

    [55] => Firefox Setup 17.0b5.exe

    [56] => Firefox Setup 16.0.exe

    [57] => Firefox Setup 16.0.2.exe

    [58] => Firefox Setup 16.0.1.exe

    [59] => Firefox Setup 15.0.exe

    [60] => Firefox Setup 15.0.1.exe

    [61] => Firefox Setup 14.0.1.exe

    [62] => Firefox Setup 13.0.exe

    [63] => Firefox Setup 13.0.1.exe

    [64] => Firefox Setup 12.0.exe

    [65] => Firefox Setup 11.0.exe

    [66] => Firefox Setup 10.0.exe

    [67] => Firefox Setup 10.0.2.exe

    [68] => Firefox Setup 10.0.1.exe

    [69] => Firefox Setup 1.5.exe

    [70] => Firefox Setup 1.5.0.9.exe

    [71] => Firefox Setup 1.5.0.8.exe

    [72] => Firefox Setup 1.5.0.7.exe

    [73] => Firefox Setup 1.5.0.6.exe

    [74] => Firefox Setup 1.5.0.5.exe

    [75] => Firefox Setup 1.5.0.4.exe

    [76] => Firefox Setup 1.5.0.3.exe

    [77] => Firefox Setup 1.5.0.2.exe

    [78] => Firefox Setup 1.5.0.12.exe

    [79] => Firefox Setup 1.5.0.1.exe

    [80] => Firefox Setup 1.0.8.exe

)

И надо его отсортировать по убыванию. В идеале должно выглядеть примерно так:

17

16.0.2

16.0.1

16.0

и т.д.

Функция natcasersort() с этим справляется отлично, но она сортирует по возрастанию.

Сам массив находится в переменной $filesff.

Идеи?