Java EE (Java Enterprise Edition) General Discussion

We are building a number of separate J2ee apps that have some common problem domain. To gain advantage of reuse there have been two suggestions:

1. Use session beans (session facade) for applications to leverage components in another application
2. applications are already layered as UI,problem domain (pd) and services integration (si) and the classes in each layer in a separate jar file. So another approach can be to have a copy of the application's pd and si jar file whose problem domain you want to leverage in your application. currently these application are POJO based (no EJB).

So debate is between (1) loosely coupled "services" or (2) tightly coupled common jars (those favouring 2 are wanting to avoid complexity overhead of EJB)