Sorting a multidimensional array in PHP - intelligent method

It is not at all easy to sort a multidimensional array.. After spending hours of time we have find out a solution for it.. check the following:

Array
(
    [0] => Array
        (
            [message_email] => test3@test.com
            [message_subject] => p message2
            [message_date] => 2011-06-02 00:00:00
            [message_id] => 4
            [message_name] => test name2
            [user_id] => 26
            [user_display] => Administrator
        )

    [1] => Array
        (
            [message_email] => test@test.com
            [message_subject] => test product sub1
            [message_date] => 2011-06-01 00:00:00
            [message_id] => 3
            [message_name] => tet name1
            [user_id] => 26
            [user_display] => Administrator
        )

)

For eg: I need to sort this multidimensional array based on the message_name
in ascending order.

So I put

$sort = "message_name";
$order_by = "asc";

$asc = create_function ('$a,$b','return strcasecmp($a["'.$sort.'"], $b["'.$sort.'"]);');

$desc = create_function ('$a,$b','return strcasecmp($b["'.$sort.'"], $a["'.$sort.'"]);');

if($order_by=="asc")

usort($rows,$asc);

else

usort($rows,$desc);




print_r($rows)




Hope this will help some one.. :)