Hello Bob and all, While checking a ticket about password-reset email, I noticed that "frontend" now runs "postfix" instead of "exim4", and the logs are in /var/log/mail.* . (you also mention it on May 7th, http://lists.gnu.org/archive/html/savannah-hackers-public/2016-05/msg00007.html )
If this is a permanent change, I'd like to update the wiki page ( http://savannah.gnu.org/maintenance/MailSystem/ ). Please let me know. thanks, - assaf