The default factory is different in Java ES 2004Q2 and Java ES 2005Q1 (6200472)

Existing deployments who do not wish to upgrade the server will have to explicitly set the property of collaboration session factory object to use the Legacy protocol implementation. In the API place the following constructor to create a ColloaborationSessionFactor: CollaborationSessionFactory factory = newCollaborationSessionFactory(“com.iplanet.im.client.api.ilMSessionFactory”);