Session and global

Hi to everybody. That's my problem: index.php contains: session_start(); $GLOBALS['HTTP_SESSION_VARS']['USERNAME']=''; and two frame: title.php and home.php in home.php there is a place where to do login. Login button send two var in post method to userlogin.php that checks if the login is correct. So update the value of $GLOBALS['HTTP_SESSION_VARS']['USERNAME']='Jonny'; continuing... header("Location: www.reloadthepagewithmysite.com") In home.php also there is a line which check if the variable USERNAME is empty or not, so it displays something as "Hi Jonny". I hope not confused you ;-P Where is the problem? Doesn't work :((( Any idea? Tnx in advance, Jonny