I'd like to create an overlay that will override the default session timeout in the web.xml of my deployed application. Is this possible to do in version 7.1.1 Final?
No, in JBoss AS 7.1.1 You will have to edit the "web.xml" and then you will need to repackage your WAR and then you will need to redeploy your application in order to get the changes reflected.
The overlay feature was introduced from JBoss AS 7.2 Means EAP 6.1.0 GA (which is built from AS 7.2) Deployment Overlays - JBoss AS 7.2 - Project Documentation Editor
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