EJB 3.0 (JEE5) allows you to configure most application settings via annotations. But EJB 3.0 also supports XML files for overriding default annotation values and configuring external resources such as database connections. So, I guess it's all a matter of choice depending on the type of metadata: for metadata that is coupled to the classes, use annotations i.e. O/R annotations. For application-level metadata i.e AOP metadata, or DB metadata, use deployment descriptors.
Still, I guess building apps on JEE5 is not as flexible as doing so on Spring, especially when it comes to configuration choices.
/M
[ April 01, 2006: Message edited by: Manuel Palacio ]
[ April 01, 2006: Message edited by: Manuel Palacio ]