系统退信
did not reach the following recipient(s):

wh@163.com Thu, 15 Apr 2010 19:05:31 +0800
  There was a SMTP communication problem with the recipient's email
server. Please contact your system administrator.
  < #5.5.0 smtp;550 Blocked by rbl>
wh@126.com on Thu, 15 Apr 2010 19:05:31 +0800
  There was a SMTP communication problem with the recipient's email
server. Please contact your system administrator.
  < #5.5.0 smtp;550 Blocked by rbl>

------解决方案--------------------
所有的都发布出去？
------解决方案--------------------
"There was a SMTP communication problem with the recipient's email server."

这一句不是说得很明显了，smtp配置错误，先直接telnet smtpserverip 25，先排除smtp 25端口的可连接性，再改smtp配置，注意要对方提供该接口才行


------解决方案--------------------
smtp;550 Blocked by rbl
被对方的反垃圾邮件系统当成垃圾邮件了,
SMTP通信断了,
不是你的问题,和对方联系要求将自己的IP从RBL里去掉,或加到白名单里,