They probably already got the patent for it, perhaps not speecificly for the N900 prototype, but there should be enough info about how it works already in the hands of the patent office(s), and since anyone can browse the contents of granted patents it shouldn't be too hard to find out what is involved in the implementation of this functionality if you know what to look for, perhaps someone could try looking for the info to see how much a stock N900 would need to be changed to have that functionality