PHP配置中的SMTP

Question

此配置有什么不好？

// smtp hostname of your server, you can use localhost if
// it is the same server.
define ("MAIL_HOST", "smtp.gmail.com");

// SMTP username of your server, it is the same like
// PASSWORD if you use the same server
define ("SMTP_USER","fname.sname15@gmail.com");

// SMTP password of your server, it is the same like
// PASSWORD if you use the same server
define ("SMTP_PASSWORD","lololololo");