Disklavier

Hello all,

I am looking at writing some Java music software that I would like to be 
able to read the ESEQ files saved from my Disklavier (and I believe also 
my SY85 and other synths).

Does anyone know of a file specification anywhere on the internet, or that 
I can get hold of from Yamaha somehow? I've spent a lot of time on google 
and not really come up with anything yet - is it going to be a matter of 
reverse engineering the format myself?

Thanks,

James