如何使用Microsoft AD为内部PHP应用程序实现单点登录(SSO) ?

I'm vaguely aware that on a computer joined to a domain IE can be asked to send some extra headers that I could use to automatically sign on to an application. I've got apache running on a windows server with mod_php. I'd like to be able to avoid the user having to log in if necessary. I've found some links talking about Kerberos and Apache modules.I'm vaguely aware that on a computer joined to