I urgently need a simple PHP script for securely logging in users to a website. Deliverables include:  Simple login/logout page.  Ability to redirect from other pages in various locations within the website (for example, /[url removed, login to view], /somefolder/[url removed, login to view]) to /[url removed, login to view] if user has not logged in, or login has expired.  Login should be valid for only 30 minutes, after which the page should redirect to /[url removed, login to view], which after the user logs back in, redirects back to the page he came from. Please send me a message for the relvant 'users' table schema and/or for clarifications.