Why would .NET suddenly try to serialize my object in my ASP.NET application?

Question

I run an Azure web role in Full IIS mode. Requests are authorized with custom basic authentication.

I have MyAssembly.CustomIdentity class that inherits

Answer 1

Is this related to the following connect bug:

https://connect.microsoft.com/VisualStudio/feedback/details/712500/cant-use-appdomains-inside-wcf-called-methods