plugin=diff is not implemented.
http://yellow.ribbon.to/~tuotehhou/index.php?%2BLinux%2B%E3%82%B7%E3%82%B9%E3%83%86%E3%83%A0%E8%A8%AD%E5%AE%9A%E6%AD%A3%E5%B8%B8%E3%81%AB%E5%8B%95%E4%BD%9C%E3%81%97%E3%81%AA%E3%81%84
plugin=diff is not implemented.