Before I just run off and do it anyway (already dissecting the auth/server message parts), I thought why not just offer - I am willing (for free) to make a LGPL-licensed XNA client. This won't take me that long since I'm familiar with it (and C#) since I do it for a living, and the game itself is simple enough (at least the client part).
Things an XNA client could offer:
Real 3D, or at least an easily manipulated 2.5D environment.
Much cleaner code.
Much improved efficiency, Java graphics always have my laptop fans running overtime despite the implied relatively low overhead.
Easily pluggable resources, although the current Java has this too.
Easily ported to XBOX (for whatever that's worth).
Also portable to Android phones (for whatever that's worth).
Things XNA cannot offer(at the moment):
Linux support (although I hear mono is trying, they're way behind on everything else though).
Direct web play (JNLP would still have to cover that).
All I would want:
Detailed explanation of server handshake, and server messages, and any details I need to parse on the client side, or at least a detailed explanation of what's going on in the Java, which I am capable of reading/coding.
That's all I need, honestly. I can and am already reverse-engineering those 2 things but I'm offering it publicly now on the off chance that you want it. I think the game itself is great, the client is obviously incremental code and even the coder admits he hates Java (although what he prefers I don't know). XNA would give the client a new fresh start, this game would barely scratch its capabilities so it would be perfect to expand on.
XNA is a Microsoft platform designed for portability between XBOX/PC/Android but it's rapidly replacing DirectX as the focus of their managed code graphics API. It has no licensing restrictions, just has an XNA redist that would be packaged along with it like DirectX.
What do you think?
My email is my username at gmail if you prefer that route.