Session Expiration Problem: How to keep a user logged in for

You need to use a cookie and use that to log the user in automatically. You can then set the cookie to expire after 2 days, 2 weeks, 2 months, …

It’s part of acts as authenticated and restful authentication, but here’s a page describing the way to do it yourself:
http://technoweenie.stikipad.com/plugins/show/Remember+Me

Best regards

Peter De Berdt