Which one of the EJB 2.1 or EJB 3.0 is better to code and understand?
I felt EJB 3.0 to be easy to develop compared to EJB2.0 for the following reasons,
1. You don't have to write Home Interface
2. You don't have to write configuration xmls and maintain them.
3. More than development its light weight unlike the EJB2.1.
Note: You need JDK 5.0+ and application server that supports EJB 3.0.
If you want to kill yourself, go for EJB 2.1 I had hard time dealing with SJAS at the time of EJB 2.1 there.