OK, try the next build (hmm, why hasn't the previous one shown up yet?).
What I did is to allow certain functions to be made optional when loading an extension. LWJGL has always been checking for the availability of all the functions in an extension (or core GL version). When one of them was missing, it would make it so that the whole extension was not available. For now, I've marked the following functions as optional:
glDrawElementsBaseVertex (GL32)
glDrawRangeElementsBaseVertex (GL32)
glDrawElementsInstancedBaseVertex (GL32)
The above 3 are missing from the current ATI driver.
glGetInteger64i_v (GL32)
This one is missing from the current NV driver.
This means that, for example, you'll be able to use all GL32 functions on an NV implementation, but calling glGetInteger64i_v will throw an exception. Hopefully the latest commit fixes both AMD and NV issues.