The timeout configuration you are referring to is the default value used for transactions. If no other timeout has been set then the transaction will timeout after this period.
This does not mean that your application terminates, only that your transaction does. The next time you attempt to do anything transactional you should receive an exception saying that the transaction is no longer valid.
What is your application doing?
Kevin, please don't answer user questions in the dev forums.
You need a user forum for user level JBossTM questions.
I've no problem with that. How do I move it across for next time? ;-)