I have a treenav control with a click handler that loads and shows a dynamic edit panel for the selected treenav item next to it.

Sometimes the error mentioned in the subject occurs. I haven't yet been able to reproduce it myself, but other people told me they had this error occur when they were working on that page for a while.

Has anyone an idea what the problem could be here? Does it happen when there is a incorrect formstate in the session? And how does it come to that and how can it be prevented?

The errors occured with qcubed version 1.x and i just recently updated to 2.0.2, but can't confirm yet that the errors are gone. nevertheless it would still be very interesting to know more about this error.