So, yesterday I was thinking about the problem of session/conversation context passivation and clustering. Currently there is no notion of a "unique id" of a Bean object, which the container would need in order to identify the session attribute holding the Bean object. In a pure-local execution model this is no big deal, since you can just generate one the first time you see a Bean. However, in a clustered environment it becomes an issue, especially when we have custom Beans provided by portable extensions. I don't see a better solution than introducing a new interface with a getId() method: interface PassivationCapable<X> extends Bean<X> { String getId(); } Instances of Bean could optionally implement PassivationCapable. We would also need to add a method to BeanManager: interface BeanManager { PassivationCapable<?> getPassivationCapableBean(String id); } WDYT? -- Gavin King gavin.king(a)gmail.com http://in.relation.to/Bloggers/Gavin http://hibernate.org http://seamframework.org