help needed with session variables

hello, I am making use of sessions in my PHp/MySQL Database application. When the user is successfully authenticated against the database, a session is created in following manner: session_register("valid_user","firstname","lastname"); $valid_user = $login; $firstname = $first_name; $lastname = $last_name; While I am able to use the $valid_user variable all thru the sesion , when I try to use the $valid_user it works fine (i.e. I am able to access the value) throughout the session, however when I try to use the other two registered session variables i.e firstname and lastname, I am not able to extract the value. Can you suggest what might be going wrong. Note I am locally testing the setup on my Mac. Many Thanks Pushpinder Singh Garcha _________________________________ Web Architect