Apart from the remotes that came with the 4000 series machines, all Replay remotes are JP1 compatible.
The remotes that came with the 2000 and 3000 series machines, and the Panasonic Showstoppers, are totally JP1 compatible and can be programmed to do what you want.
The very early Replay remotes, the ones that look like the Cinema 7 are not JP1 compatible.
The remotes that come with the new 5000 units are JP1 compatible, but there's not much you can do with them at this point. Maybe in the future someone within the JP1 group might develop some software to make them more universal, but that's not likely to happen soon.
Just FYI, the JP1 group was primarily founded by ReplayTV users.
Rob
http://www.hifi-remote.com