I'm working on packaging up the first release of my Nebia project. I use a combination of IDEA and Ant to do my building.
I've liked what I hear about the Apache Groups Maven tool.
I like the general idea of it, but just like Mike Cannon-Brookes I have had some problems with it.
My main problem is integrating dependencies that aren't in ibiblio.org
I don't have a lot of time to play with it, so I've come to the compromise that I use Ant to build it and maven to generate the documentation. Its not ideal but I'm sure I'll get the rest working at some point.