I checked this support ticket #605834 . Customer was disabled the ViewState.
That was causing the issue. Can you verify that your ViewState is enabled?
I followed your steps to created small sample, but couldn't reproduce the issue. I have tested with
2011.1.519.35 and 2012.3.1205.35 on latest Chrome (ver. 24), IE9 and FF18. Please look at my sample and modify it in order to reproduce this behavior. Maybe this happens only on a particular browser version.
Note that .dll files are removed from the sample.
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