function zeroFill(&$array)
 {
     // PHP 5 only function used here
     if (function_exists("array_walk_recursive")) {
         array_walk_recursive($array, array($this, 'addzero'));
     } else {
         owa_lib::array_walk_recursive($array, array(get_class($this) . 'Metric', 'addzero'));
     }
     return $array;
 }