You will have to provide us more details about your setup and the exception. When does this exception occur? The entire exception stacktrace. Also please provide the version of Java and exact version of JBoss. What is your application? How is it packaged and how is it deployed?
While posting the logs or xml content or code, remember to wrap it in a code block using the Code button in the message editor window and please hit the Preview button to make sure your post is correctly formatted