"Remember me" checkbox in login screen

The login screen has a "Remember me" checkbox.
When this box is selected by the user before logging in, a unique key is generated after logging in succeeded.
This key is stored in both the user preferences in the repository, and in a cookie on the user's machine.
When the user visits the login screen, it checks whether the user has a key in a cookie available, and matches it against all users in the repository.
If a matching user is found, the "Username" field is automatically propagated with the user's login and the "Password" is propagated with a fake *** password.
When the user clicks the Login button, he is automatically logged in (without a password).

We do want to have the explicit login button press. (the system is not automatically logging in without the user having to press the login button)