Authentication problem

I have come across a very weird situation. I made a slight modification to
our authentication process to allow a single deployed website to
authenticate a user with either forms authentication (if coming from an
unknown network, such as the internet) or windows authentication (if coming
from our own internal network). Everything is working fine, and the
authentication is working exaclty as expected. However, a weird side effect
is that once authenticated, the IsPostBack property will now only return
False, and event handler methods like Button.Click are not called.

This occurs even though the server variable REQUEST_METHOD is returning a
POST when a post back event, such as a button click, occur.

Sorry for the cross-post, but I'm not sure what category this problem falls
in. Has anybody ever experienced a situation where the IsPostBack = False
even though Request.ServerVariables("REQUEST_METHOD") = "POST"??



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