JBoss Cache uses the older Doug Lea concurrent library which throws InterruptedException from all lock methods if the thread was interrupted. The newer 1.5 concurrent methods mostly don't do this. It's mostly done as a favor. If a thread is interrupted, typically the purpose of this interrupt is for timely shutdown of the thread. Regarding the exception thrown, any method in Java can throw a RuntimeException, which is what is happening here. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4071744#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...