==== 提供基本信息便于分析问题并得到快速回复 ====
- iRedMail 版本：
- 使用的 Linux/BSD 发行版名称及版本号：
- 与您的问题相关的日志信息：
====

This is the mail system at host mail.sklse.org.

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.

                   The mail system

<xxxxxx@qq.com>: host mx3.qq.com[113.108.18.210] said: 550 Connection
    frequency limited.
    http://service.mail.qq.com/cgi-bin/help … no=1000722 (in
    reply to RCPT TO command)
Reporting-MTA: dns; mail.xxx.org
X-Postfix-Queue-ID: 2871529087F
X-Postfix-Sender: rfc822; www@xxx.org
Arrival-Date: Thu, 19 Jul 2012 08:58:24 +0800 (CST)

Final-Recipient: rfc822;xxxxx@qq.com
Original-Recipient: rfc822;xxxxx@qq.com
Action: failed
Status: 5.0.0
Remote-MTA: dns; mx3.qq.com
Diagnostic-Code: smtp; 550 Connection frequency limited.
    http://service.mail.qq.com/cgi-bin/help … no=1000722

我查看qq的帮助说是我的服务器IP被禁，这是怎么回事啊？如何才能解决？
向163的邮箱发邮件也会导致同样问题。但是可以向yahoo 126等邮箱发送。
请工程师帮忙啊，谢谢