still on sessions

alrigh I have switched everything over to the $_Session['variable'] style of session. Next question, I have a little script that used to check if the session was registered and if it was not it would redirect to the login page. How do i accomplish this now that i cannot check if the session is registered? Here is what i have. <? session_start(); if (session_registered("valid_user2')) { echo " you are registered"; } else { header("Location: http://loginpage.com"); } ?> How do I check if a session is active/registered or whatever it is so i cn still redirect or assign variables? _________________________________________________________________ Join the world’s largest e-mail service with MSN Hotmail. http://www.hotmail.com