Redmine

Hi.
I have a small problem and I have not found how to solve.
With some Ajax request, application controller say 401 unauthorized ans a pop up is display to login.
But login and password don't work on this pop up.
I have 401 because session was closed.
It's easy to reproduce even on this website.
Logon, click on new issue.
Right click on logout and select open on new issue.
Come back to the first issue and try to change tracker.
A pop up is display because browser receive 401 error.

My question it's: How can I do to hide the pop up and redirect user on login page ?
Or make than the user name and password entered on the pop up, create new session to allow continued