Thanks to kenyob for this comment:
“Is there any Palm Pilot Compatible version of this game? The whole interface is there with the touch screen and direction button on the bottom. Someone needs to make a version for all the Treo’s and Palm TX’s out there quickly.”
Sadly the short answer is no, Jam Sessions won’t run on the Palm platform. However, there is a developer looking to create a DS emulator for the Palm platform, I’ve no idea when (or if) it will arrive, but that’s the only real hope there is.
If anything develops on the DS emulator I will post on it.