I am facing the same problem of deserialization of user objects.But when I copy the user jar file in userlib folder under jbpm within server I get Class cast exception.. like
java.lang.ClassCastException: com.jbpm.java.sample.StudentType cannot be cast to com.jbpm.java.sample.StudentType
which I feel is again due to conflict in class loading. How can I get over this issue.
Puneet