I would be in favor of moving to Maven. This year we moved about 30 projects from Ant to Maven. There are some gotchas though (disclaimer - I'm not the expert). One that I am aware of is the artifact per project preference of Maven that, as others pointed out, would pose a challenge for the Jini jar service pairs. Another side-effect of this constraint is how it interacts with Eclipse which does not support subprojects well. We have found that some thought is required to use Maven seamlessly within Eclipse. It's doable, but if you just do the obvious thing you might have a lot of problems.
All that said, we have great benefits from Maven. Sean
