Update: All fixed now.
I just installed a kernel update on our rsync and mail server and it seems we have broken hardware so it is unable to reboot right now. Mailing lists are running on a different system however you need to use the lists.archlinux.org domain rather than archlinux.org. So for arch-general you'd use arch-general@lists.archlinux.org. Mails sent to the normal domain will go through once the server is up again.
The rsync master will stay unavailable for now.
I've asked the hoster to look into the issue, but I can't currently estimate when I'll get a reply/fix.
Sorry for the inconvenience, Florian