I managed to get around the other problem with DBCP by removing the implements Serializable from the connection pooling bean. Now I am left with a problem I can't solve though as I cannot affect the: org.apache.catalina.session.StandardSessionFacade
Each of my beans have an init() method that takes ServletContext and HttpSession as parameters so that they can call other beans at these levels. Are these the Sessions that I am being asked to serialize or remove?