Yeah the older free source might do the trick.
I was thinking more of something like: http://luacraft.com/
(hence my lua hints)
that would probably require less wheel reinventing and is already a working product - I know - I use it.
I own and have paid for every minecraft license ever requested of me, including the 4J port and dont feel messing around getting his LICENSED software onto the kindles is a big issue. You have to buy it to run it anyway.
But for testing yes we could run the older server code also.
Any further thoughts after these revelations?