例 11.8. 增加邮件头信息
<?php
require_once 'Zend/Mail.php';
$mail = new Zend_Mail();
$mail->addHeader('X-MailGenerator', 'MyCoolApplication');
$mail->addHeader('X-greetingsTo', 'Mom', true); // multiple values
$mail->addHeader('X-greetingsTo', 'Dad', true);
?>