ASP.NET Impersonation ... WCF Identity... EASY Question. :P

I'm messing around with ASP.NET & WCF.  I have a simple IIS site with Windows authentication on.  HttpContext.Current.User.Identity.Name reports my windows logon.  However, when I call a WCF service, the identity it gets is NETWORK SERVICE (which is the identity of the app pool my IIS is running under).

Why is this so? :P  I have to set identity impersonate=true or impersonate in my method call to make it work as expected.  Also, I can't find NETWORK SERVICE anywhere in my session.  The current thread's principal is set to my user account. Where is this identity stored?

 

Thanks :)

Michael
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