SSO issue in VCSA 6

I have just recently installed VCSA 6.  I have configured AD authentication and it is working well.  The issue I am having is that in the web interface, when I have the "Use Windows session authentication" box checked, the username is filled in with the down-level logon (domain\username) and not the UPN (username@domain).  Is there a place I can force windows to use UP rather than down-level logon?

Thanks,