Forms authentication after a user session has expired
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I have an asp Login control in a jQueryUI dialog box that is hidden until a user's session is near or has already passed expiration. I'm reading a custom field in the aspxauth cookie from client script to display an "extend your session" message, which if the user clicks, sends an async XHR to the server which returns cookies with updated values. All of this is working fine. My problem comes when a user does not respond to the "extend session" message and their session expires. They then see the jQuery dialog with the Login control which should allow them to authenticate without taking them to the default login page. When a user submits their credentials via the login control is takes them to the default login page and does not authenticate them. What do?

 - I am not using ASP.NET AJAX
 - I have implemented the FormsAuthentication_OnAuthenticate event in the Global.asax, so I do have access to the FormsAuthenticationEventArgs object there if that helps.
