Excluding and re-including fixed it. But then I was having problems with the switch not functioning properly. No matter what I changed in the preferences, I could not get the relay to disable. I am just using it as a scene controller to control some lamps in our bedroom that are plugged into a Zwave plug.
I was able to get it working by using @bcopeland's Zen21 driver found here. So I think there is a bug in the built-in driver for the Zen21 running firmware 3.4. It was working fine when I was on 3.1.
