I think my shell server is having trouble talking to the BYOND hub. I can connect to worlds with client/authenticate set to 0, but other worlds fail to connect (it just sits there trying to connect for a while or drops it and shows security certificate failed in the world log). I can ping hub.byond.com from the server. I've also tried the last 5 or so versions of BYOND (468 is currently installed).

The server was an Ubuntu 9.10 install, and this behavior just seemed to occur out of the blue about a month ago. I wiped it and did a clean install of Ubuntu 10.04 yesterday but the problem persists. It's a VPS from Linode.

Any ideas on what the source of the problem is? Or would somebody mind assisting me in troubleshooting it?