plugin=diff is not implemented.
http://yellow.ribbon.to/~tuotehhou/index.php?%2BIIS%2BIIS7%E3%81%B8PHP5%E3%81%AE%E3%82%A4%E3%83%B3%E3%82%B9%E3%83%88%E3%83%BC%E3%83%AB
plugin=diff is not implemented.