Hello John Hunter,
Thank you for getting back to me.
I have managed to reproduce the problem when using a control which is not an Ajax control (for example ASP.NET Button). However this scenario does not reproduce if you use an Ajax control (e.g. RadButton). We are going to upgrade the RadControls for ASP.NET Ajax to Q3 2010 this week and the upgraded controls will make it into this Friday's release. Then you will be able to use RadButton instead of ASP.NET Button.
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