Changing a DataSource to STS=1

Hi. 

We are going to change our DataSource configuration, so users now can use the IMS Login.

Currently only set for Domain login (STS=0) All users set as Domain login.

If I set STS=1 (SSO=1 already set)

Doing this, the Domain login kind of disappears.

The login expects, that user has set the Federated Identity name (E-mail).

If this has not been set, just double clicking on the DataSource, we see the login dialog box. So no longer an automatic Domain login.

Even after a successful login, a logout, and a new login, we see the active Login dialog box.

If Identity Name is set, the Double click works, but now as an IMS (but user has not been changed to Federated (still Domain)?

Why is the Domain Login not preserved. No user settings have been changed (Type 'Windows' still active with correct Domain set) ?

Regards Christian