“永久性传递失败”的问题

su-min

最近给XXX@51job.com，XXX@hotmail.com等邮箱发送邮件一直被退回，但是163，腾讯等邮箱发送邮件没有问题，求高人指点，跪谢！！！
提示码如下：


The attached message had PERMANENT fatal delivery errors!

After one or more unsuccessful delivery attempts the attached message has
been removed from the mail queue on this server.  The number and frequency
of delivery attempts are determined by local configuration parameters.

YOUR MESSAGE WAS NOT DELIVERED TO ONE OR MORE RECIPIENTS!

Failed address: XXX@hotmail.com
: Óʼþ°üº¬[1]¸ö¸½¼þ

麻烦高人给小弟指点一下，我们是公司内部的MD邮件服务器，个人认为是对方把我的域名屏蔽了，求解！！

su-min

自己顶一下，在线坐等高人指点……