Delegating Credentials from the TMG Firewall by Sending only Username
You may have run into situations where you want to publish a web server through the TMG firewall and have the TMG firewall only delegate the user name instead of the domain\username format.
How do you do that?
You can change the web server behavior or the firewall behavior. Since we might not be able to control the web server, we’ll have to focus on the firewall.
Check out this article on how you get the TMG firewall to change its evil ways
DEBRA LITTLEJOHN SHINDER
MVP (Enterprise Security)