My application is running on Ubuntu.
I noticed that when I enabled logging in the Acceptor Thread area of the admin console (Under Http Service) the application suddenly sprang to life! This leads me to believe that the acceptor thread had perhaps died, and changing a setting caused it to reset. I'm certain that the domain did not stop and restart. This is only a theory however. I am going to try increasing the number of acceptor threads, although I know that really you should not need more than one per CPU on the machine.
[Message sent by forum member 'kevinmacdonald' (kevinmacdonald)]
http://forums.java.net/jive/thread.jspa?messageID=271643