Thanks Maciej,
please find the attached files for the main program and the process definition I used.
If I comment out the Line 94,
ksession = JPAKnowledgeService.newStatefulKnowledgeSession(kbase, null, env);
use
ksession = kbase.newStatefulKnowledgeSession();
the process works fine, but I do need the process instance persisted for future usage.
Ted