用iredos架设系统，使用一段时间感觉很稳定。
请教一个问题，最近发现退信的mail server host地址错误，估计是架设时输入错误造成。请教高手修改哪些文件可以改正过来。
其中www.ir-tech.asia是想修改的地方

以下为退信部分内容
From: Mail Delivery System [mailto:MAILER-DAEMON@www.ir-tech.asia]
Subject: [SPAM]Undelivered Mail Returned to Sender

This is the mail system at host www.ir-tech.asia.

I'm sorry to have to inform you that your message could not be delivered to
one or more recipients. It's attached below.

For further assistance, please send mail to postmaster.

If you do so, please include this problem report. You can delete your own
text from the attached returned message.