Doug:
It wasn't but somewhere along the way it has snuck in with a core change of the code and will be fixed in the next release. I'm close to a beta but have one other bug to fix that requires me to setup a second domain @ home and have been having issues with getting the time to do just that.

More information on the issue you're seeing can be found in this post.... http://www.dotnetnuke.com/Resources/Forums/forumid/89/threadid/418470/scope/posts.aspx

Alan
Apologies for not replying sooner. Not sure why your post slipped past me or my email other than September was a madhouse here at work.
The Active Directory provider is intended to work as a Forms -> Windows Authentication. That is it's purpose. If you want Windows Authentication only then you would change your web.config from Forms authentication to Windows authentication. What else you have to do afterwords I don't know as I've never used it. For what it's worth only domain users can log into the site we use at the college I work for and using the AD provider under Forms authentication has worked fine for the past 5 years.

Mike Sirois:
Same apology to you as to Alan.
Did you get this sorted out? If not let me know and we can try to figure it out.

It's resolved. I just need to get the multi-domain issue sorted out http://dnnauthad.codeplex.com/workitem/6984 and I can release a beta.