This is something that Apple is currently investigating. Here is a workaround, so you can beam cards between Newton 2.0 and 1.3 OS devices.
1) On the Newton 2.0 OS device, open the Extras drawer and tap on Owner Info.
2) Check the owner.
3) Tap on the routing button, and then tap on "Beam". DO NOT tap on "Beam My Card."
4) On the Newton 1.3 OS device, open the Extras drawer, and tap on "In Box".
5) Tap the Receive button, then tap on "Beam".