Hello, My Question is, how i can install more then one database in the Embeddable EJB Container and then switch between them via Seam? All the databases have the same database schema, and therefore the same entity bean Mapping classes per Table in the source code(Mabye one single database has a subset of it, but thats not a must). So for one database theres no problem in configure the jboss-beans.xml like this: ... org.hsqldb.jdbcDriver jdbc:hsqldb:. sa java:/DefaultDS 0 10 1000 50000 ... and int the persistence.xml i configure an persistence-unit like this: <persistence-unit name="manager1"> <jta-data-source>java:/DefaultDS</jta-data-source> </persistence-unit> if i deploy my application, then the Tomcat 6.0 Server binds the Name for the Database automatically and maps the Tables to the corresponding entity Classes also automatically. So now i have tried to configure a second database. I have extended the jboss-beans.xml , and persistence.xml to configure a second bean and second persistence unit, for the second database. And in my Session Beans i refer to the second persistence unit, like that: @Persistencecontext(unit-name="nameOfSecondPersistenceUnit") Entitymanager em; But this doesn't work. if i looked at the logs from the Tomcat server, then i saw that the Entity Bean Mappings only made for the first Database, but not for the second. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4089950#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...