OpenEJB has been around for seven years and is one of the few standalone and
embeddable EJB containers. Useful mainly for unit testing EJB beans
(embedding the containers in unit tests), OpenEJB is also available as a
Tomcat plug-in. Which means you can call EJB beans from your Web
application's servlets. This fact alone opens up new possibilities for
migrating current Web applications to JEE 5 in addition to facilitating
development and testing using the popular Apache Tomcat server instead of a
full JEE application server, even if you eventually deploy to a dedicated JEE
application server. OpenEJB 3 supports JPA out-of-the-box (and CMP by mapping
to JPA) and uses the Apache OpenJPA implementation. JMS support is also
included in ActiveMQ and recently Web Services annotation support has been
added to hook up with a Web service provider like Axis2. There's built-in... (more)