Vaadin 7 project not able to launch on JBoss AS 5.1 But working on Apache T

I am working with Vaadin 7, created basic app (whatever start new project gives) and exported it in .war file and tried to deploy on JBoss AS 5.1 and Apache Tomcat 7.0.
Deployed successfully on both.
But working on Tomcat only and not on JBoss. On Jboss it’s not even showing logs statements for application launch.

What web page shows when hitting url is — HTTP STATUS 404 - resource not available it’s showing.

Any help appreciated.