Every month, PEAR developers receive a mail from pear.php.net containing a list of open bugs and feature requests for their packages.
Last month, my mail listed a feature request as "open" although I had set it to "won't fix" a week before. I put it on my TODO list, but did not have the time to investigate further.
This month, Craig Constantine sent a mail to the PEAR developer mailing list, asking why he was receiving mails although he was inactive. Nobody knew. People on #pear began to investigate: Checking the code, executing the code on our lovely CI server with a copy of the live data.
Nothing. Not the slightest trace of a problem, except for those mails. We were clueless until someone asked if the mails were really coming from our database - and our server. A look at the mail headers shed light on the problem: The mails had been sent from pb12.
pb12 hosted pear.php.net unil January 2009, when we ditched it for the new euk1 box. After moving the website, nobody actually removed the pearweb code, database or cron jobs - and nobody setup the reminder cronjob on the new server, letting the issue go unnoted.
We were really getting messages from the past - from an old system that was forgotten, but still running.