AntiXSS and Request Validation

Hi,

I've recently upgraded my web application from ASP .NET MVC 3 to ASP .NET 4.5.  I see that ASP.NET 4.5 now includes the AntiXSS library, and it can be included by modifying the encoderType attribute of the httpRuntime element. 

If I turn this on, what happes to request validation (http://msdn.microsoft.com/en-us/library/hh882339.aspx)?  Do the two libraries co-exist?

Thank you,
Notre
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