When upgrading from JES5 (Application Server 8.2) to Application Server 9.1, the Portal Server Community sample no longer works, and throws many javax.faces.application.ApplicationFactory errors.
Upgrading from Application Server 8.2 to 9.1 is not supported if Application Server 8.2 was installed with the JES5 Portal Server. Portal Server needs to be upgraded to Java ES 5 Update 1 prior the Application Server upgrade to 9.1.