I made a small breakthrough in how to build LWJGL for ARM.

I'm going to try it soon then post results. My initial attempt in scratchbox failed so I'm going to try and compile it with a different cross compilation environment.

Update:

It seems that Java can't run in the scratchbox (which is why I get errors. QEMU errors if anyone's interested) so I've decided to compile it directly on the device.

I'm getting a lot of errors thrown at me but I'm working my way through them. Luckily so far it's only missing dependencies such as X11 stuff, GCC etc.

I think I'm narrowing it down now so it's possible that there will be an ARM LWJGL library soon!

Update 2:

Success! I have compiled lwjgl.so for ARM Linux successfully. I'm going to re-install Sun Java onto my N900 so that I can test Minecraft with the new library.