ESXi 4.1 Update 2 and AD Authentication

Hello,

I am running ESXi 4.1 Update 2 (stand alone).  I would like to integrate it with my Active Directory.

I am able to join it to the domain just fine under "Authentication" services.  When I go to the Permissions tab of the server and go to add a new permission, I can search for the users and groups in my active directory.  What I cannot seem to do is add the user or group to the permissions.  I get the following error:

Does anyone have any ideas on getting around this?