Sudden and unexpected shutdown of JBoss

[perseus]

I have deployed a web/ejb application in jboss (size of EAR 1.5MB) and I'm using Apache 2.0 with Ajp13 before. The previous version (EAR 1.4MB) works fine for several weeks in production. Now I've added some new features and we face a very strange behaviour of the Jboss server.

After two round about 2 hours online the JBoss server performs a shutdown without any visible reason. It's not crash or exception. The only message in the logs with full tracing enabled is:
Shutdown 48 MBeans and so on and then the server is going down gracefully.

What are the reasons for JBoss to perform a shutdown himself?
How to find out more about the reason?

Thanks for any comments.

[raja05]

There are quite a few reasons why this could happen
1. Some TERM signal sent to the jboss jvm.
2. Space constraints on that box, for e.g. jboss trying to write to a temporary location and not able to do it.

are there any environmental changes that you suspect could cause this?