I have recently been using the J2EE component of Intellij and I think that
integrating Xdoclet would be a huge plus for J2EE development.
The current EJB management screen could be kept, but they could generate a
single Java code file containing the code to generate by the XDoclet
This would simplify the maintenance of the EJB code, avoid out of sync
change between the various files, etc.
IDEA could even autogenerate the Xdoclet file when compiling the project
and add the necessary code for build from the generated Ant script.
For now, I think Xdoclet integration is not as easy as it should be.