I am thinking about a platform for study application (it is team work). I mean standard Java EE 5 (or maybe try raw Java EE 6) and Spring. What is your choose? (I don't mean Spring MVC but Spring Beans and EJB 3.0)
Also I would like to know what app server you use? (now I use GlassFish v2)
I would recommend Spring without EJBs.
My favorite choice of Java EE app server is WebLogic, but I don't know if Oracle is as generous as BEA was about making it available to developers.
I'd recommend using Tomcat as your app server. If you need JMS, add ActiveMQ.