Has anyone else encountered complaints from users about confirmation URLs not working that can't be explained by them expiring or having been done twice by the user? The user is told that the confirmation number is not valid, but the command is, in fact, confirmed. The LISTSERV log shows two confirmations, one right after the other. The user gets only the error message from the second. We can't reproduce the problem, but it seems to occur every several days. I have actually seen it happen myself. We are running LISTSERV 1.8d on Solaris 2.6.