Thanks for the quick replys everyone.
I guess I didn't give enough information in my original post (sorry bout that) so I'll try and clear up everything:
a) I will need 3 dimensions but the game is done in 2D, with the X and Y axies representing left/right and backwards/forwards respectively, up and down being represented by going in and out of the screen i.e. faked by moving shadows - however the calculations are done as normal. So I won't be needing any scene-graph or anything like that. In short the game is 2D not 3D.
b) I've pretty much ruled out ODEJava because as a noob some unexplainable error (that's not even my fault) might be too much for me to recover from and I really want something that's all Java.
c) Is there anywhere I can just get the JOODE JAR because I have no idea how to use subversion (even though I really should by now), ahem!!
That should be about it (for now) , thanks!!