I will have to test against android 2.2 and let you know. I will get back to you soon.
Update: I fired up an Android 2.2 Froyo emulator and tried this out. Seems the run-once ran without issues. Based on your description I am a bit confused when the error is occuring. Are you able to change into the runonce page? If so, is the error occuring after you hit submit?
If it’s the second one (error submitting), it seems like a jQuery mobile issue since I don’t show a spinner on submission only on page request. If it happening during the opening of the runonce page then most likely some incompatible javascript on my part. Let me know which end so we can dive deeper into this issue. Thanks!