0xd06 error when a long username is used

[bolkedebruin]

While experimenting with SSO tokensin the username field I noticed that with long usernames (dont know exactly the number) the MS clients will report error 0xD06 and disconnect. This seems due to the fact that the login screen doesn't properly take care of these long usernames as it shows artefacts (sometimes the client reports an error, but then still connects and shows the login screen).