thinphp3.1.2链接数据库问题

[象程序]

mysqlnd cannot connect to MySQL 4.1+ using the old insecure authentication. Please use an administration tool to reset your password with the command SET PASSWORD = PASSWORD('your_existing_password'). This will store a new, and more secure, hash value in mysql.user. If this user is used in other scripts executed by PHP 5.2 or earlier you might need to remove the old-passwords flag from your my.cnf file

别人发过来的thinkphp3.1.2怎么，配置过后提示上面问题
网上查了修改密码就了，我执行下面代码后重启服务问题任在。缓存也清除
SET old_passwords = 0;
UPDATE mysql.user SET Password = PASSWORD('root') WHERE User = 'root';
SELECT LENGTH(Password) FROM mysql.user WHERE User = 'root';
FLUSH PRIVILEGES;

到底什么问题？有什么方法可以解决？
解决后立马解贴

[黄袍披身]

MySQL 4.1.... 我建议升级MYSQL 的版本...