http://www.phpro.org/tutorials/Introduction-to-PHP-PDO.html#7.2
http://henryranch.net/software/ease-into-sqlite-3-with-php-and-pdo/
http://cn2.php.net/manual/en/book.hash.php
http://www.enet.com.cn/article/2005/0217/A20050217390810.shtml
http://email.about.com/od/emailprogrammingtips/qt/PHP_Email_SMTP_Authentication.htm
