I hope you didn't get too excited when you saw this topic
I've gotten many requests to make support for the XIM 4. But from what I've seen the XIM 4 is way too inconsistent to be integrated into the calculator. Pretty much all games have some form of smoothing or acceleration (both positive and negative), and it's in general just a mess at the moment.
Should Sony or Microsoft release native support for keyboard and mouse, I'll look at this again! I hope they do, because that opens up a whole new use for this site!