Authentication, Am I still logged in?

I have a ASP.NET 3.5 web application.

I have a LoginName and a LoginStatus control in the sites master page.

When the session expires it kicks me back to the login page, but the LoginName control still say my logged in name and the LoginStatus says 'logout' as if I am still logged in?

How do I get them to reurn to the pre log in state? Am i still logged in?

How do I 'unauthenticate' the logged in user when session expires?

Isnt this wrong?

Thanks
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