Security Breach!

I have a problem with the security of this version; tell me if it’s just my computer. After logging in and taking care of ‘admin stuff’, I close the browser. When I reopen a browser and look through my History, I can access all of the admin pages without having to enter a password. This could be very bad if I login from a public computer.
I think it would make it much more secure to have all of the admin pages in a password protected directory.

That is why you always use the "log out" link, it kills the session. Then if you try to surf to it from your history, you will not be able to get in.