PageLocker plugin: how to stop the session?

Hi!
How can I stop the PageLocker session? For example, I have some secret password-protected pages on my site. I enter the password, load a page, read it for some time, then, when I read all I wanted, I go somewhere. Another man comes up to my (or not my) PC, enters a path to the secret zone (e.g. www.mysite.com/secretpage) and has the access to it without knowing the password.
So, that's why I need to have some link that would do the "exit" command, stop my session in secret zone.
Is there a way to do that?