Perhaps this article helps you:
Using Windows and Forms Authentication Together
http://www.dotnetbips.com/displayarticle.aspx?id=201

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Teemu Keiski
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Mansoft tietotekniikka Oy
http://www.mansoft.fi
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> I have an application where I would like to present a nice HTML based
> login page but log the user in using Windows Authentication.
[quoted text clipped - 8 lines]
>
> Mike