[olpc-help] how can I redefine the game keys

[dlang]

I would like to redefine the game keys (ideally on a per application basis) to make use in tablet mode easier. 

can the game keys be used in combination? (for example, have rotate+check do the rotation freeing up three additional key combinations rotate+square, rotate+X, rotate+circle)

any suggestions on how to get started? 
would/could this involve writing a program to listen for keystroke combinations and outputting the new 'correct' command?
does X already include this sort of capability and I just don't know about it?