Perhaps in the future LW will work on it. I know that right now, things are very hectic at LimePeer. They're got several bugs in the their UltraPeer system. They are all fixable, though.
:-D
A major problem they have too is the Mac version. It doesn't save files correctly, and people can't open them. Once these things are out of the way, perhaps they'll have time to do pong-caching.

:-)