Depends on where you place your configuration files in your WAR. Paste it into WEB-INF or META-INF, you will not be able to drive through them.
/app/WEB-INF/web.xml provides HTTP 404.
If there is some other exploit that would allow someone to access files on the server, I would say that it is no more secure in the WAR in the right place, and then outside the WAR file.