Ideas:
1) how about driving the entire thing with Sharepoint?
2) if you control all the sub=sites... then treat it as a single web app.
Use DNS to map it all instead of using IIS to map.
3) Passport
4) Configure Active Directory to handle auth/auth for you (requires user to
be a member of a known domain)
5) Install a commercial single-sign-on tool on your web site (Sharepoint is
simpler).

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--- Nick Malik [Microsoft]
MCSD, CFPS, Certified Scrummaster
http://blogs.msdn.com/nickmalik
Disclaimer: Opinions expressed in this forum are my own, and not
representative of my employer.
I do not answer questions on behalf of my employer. I'm just a
programmer helping programmers.
--
> Hi all
>
[quoted text clipped - 10 lines]
>
> Lino