When I click the Spell Check button on the editor toolbar, I get the following error:

 

 A potentiall dangerous Request.Form value was detected from the client (CurrentText="my content here")

 

My web app is using .Net Framework 4.0, if I change it to 3.5 the spell check opens fine.  I have tried turning off request validation for the app (instead of just the spell checker) and I get the same results. My app is leveraging a few .net 4.0 features, so this kind of gets in the way. Anyone found the right .NET 4.0 config for calling spell check from the editor?