I'm using courier 0.42.2 on my mail server and have been having a problem sending mail to one or more of Postini's mail servers. It looks as if the problem server on the Postini end is responding properly up until the final "." (EOM) and then failing to respond, or Courier is failing to recognize the response. The message is delivered complete to the recipient, but the Courier log files report:

Dec 13 14:53:10 bailey courieresmtp:
id=0000007C.41BDDC7B.000061A2,from=<fmo...@fmp.com>,addr=<song...@psknet.com>:
Connection timed out Dec 13 14:53:10 bailey courieresmtp:
id=0000007C.41BDDC7B.000061A2,from=<fmo...@fmp.com>,addr=<song...@psknet.com>,status:
deferred

The result is that the recipient ends up getting repeated copies of the email until my courier server times out on retries and deletes the messages from the queue.

This problem comes and goes. An address which was having problems yesterday seems to be working today, and I'm getting reports from one of my list admins that now other addresses of people with ISP which use Postini are having the same problem. This just started a few days ago. The Postini customers don't seem to be having any problems with mail from other correspondents, and I'm not seeing this behavior from with any other receiving systems except for Postini servers.

Has anyone else seen this?