FDD stands for Feature Driven Development and is an iterative software development process which is embedded in an Project Management environment.
It build around a domain object model and so called feature lists which are the heart for any project management plans. It starts from the requirements specification and end with a user tangible feature. There is nothing special about J2EE in it, because it lets you break down your requirements into any technical aspects you want. Actually it expects that you bring in your technical expertise be it J2EE or J2SE.
I've used Feature Driven Design. Peter Coad spoke about it in his book Java Modelling in Color. I find it to be particularly effective in larger groups of developers, where some of the benefits of XP tend to get obfuscated.