function roundDurationUp($duration_string='') {
     $parts = explode(':', $duration_string);
     // only deal with valid duration strings
     if (count($parts) != 3)
       return 0;

     // round the seconds up to minutes
     if ($parts[2] > 30)
       $parts[1]++;

     // round the minutes up to hours
     if ($parts[1] > 30)
       $parts[0]++;

     return $parts[0];
    }