$(md("你想要加密的字符串"));
md5插件下载地址：
http://xiazai.jb51.net/201003/yuanma/jquery_md5.rar
下面是我的简单例子
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title></title>
<script type="text/javascript" src="Scripts/jquery-1.3.2.min.js"></script>
<script type="text/javascript" src="Scripts/jquery.md5.js"></script>
<script type="text/javascript">
alert($.md5("Hello"));
</script>
</head>
<body>
</body>
</html>