gistfile1.php

<?php
/*
$pages is an array of assoc arrays containing all of the menu items
$id is the page to be moved
$matches[2] is the direction
*/

$len = count($pages);
for ($i=0; $i < $len; $i++) 
{ 
    if($pages[$i]["ID"] == $id)
    {
        if($matches[2] == "up")
        {
            $tmp = $pages[$i];
            $nkey = (int)$i-1;
            $pages[$i] = $pages[$nkey];
            $pages[$nkey] = $tmp;
        }
        else
        {
            $tmp = $pages[$i];
            $nkey = (int)$i+1;
            $pages[$i] = $pages[$nkey];
            $pages[$nkey] = $tmp;
        }
        break;
    }
}