As a matter of fact I got this, and this is a new one on me, when waiting for the arcade.
message_die() was called multiple times. This isn't supposed to happen. Was message_die() used in page_tail.php?
The Arcade is a complicated mess of PHP code and unfortunately the Author who was developing a PHP 3.0 version has bailed on the project as far as I can tell.
I dont think there will ever be an update to the Arcade which runs on a separate PHP 2.0 installation.
There are some other Arcade mods being developed for PHP 3.0, but I would dread trying to move all our games over to a new mod.
So I am not sure what to do with the Arcade as we move forward, I still have hundreds of games that I can add as well.