Authentication in SSO and trasparent mode with authentication whit browser.

Hi all,
I have a question.
A customer have activated a web filtering profile authenticate with AD in SSO and work fine.
Together have,for the guest, in Fallback action default filter action the authentication mode browser in trasparent mode.
The problem is: if the administrator of the Astaro change the password of an user for the authentication via browser work fine both the password,the new and the old .....
A other problem is that the pop up page with the logout option not appear.
Because ?

Thank you

Luca