There are two options for serialization: j2ee or Lucee. Simply put, the Lucee option works in a cluster using database persistence and the j2ee option simply cannot work in a cluster no matter what architecture is chosen (DB persistence, multicast, Memcache … ).
It really looks like the issue is because the class “JSession”, that lucee stores in the session, is not available to the class loader, not even if the lucee jar is made available to the j2ee container (Tomcat in our case). The actual error is a class not found. Something screwy is going on with the class naming or serialization here. When tomcat manages session serialization then tomcat needs any class used in the process to be available to its class loader.
This issue has been touched on before but not really addressed so can correcting j2ee serialization become a fix? There are many ways of course to correct this issue including making the JSession class public and available or serializing the JSession class as String and unmarshalling it later.