note 17915 rejected from function.session-id by irc-html

//login.php session_id(md5(uniqid(rand(),1))); session_start(); header("Location: index.php"); //logout.php session_start(); session_unset(); session_destroy(); //session_id destroyed after my checking header("Location: index.php"); //index.php if (session_id()) : echo "hello"; else : echo "bye"; i found that the session_id() works fine in the login.php and logout.php however, after logout and forward to index.php, the session_id remains here and "hello" is appeared Can i destroy the session_id?? i found that there is the problem is solved when i use other variables and use session_register() instead e.g. session_register("login"); Is that means session_id is useless??