Session Problem, Please Help.....

Dear all, I have a strange problem: I'm using IIS / WINNT4, PHP4 Please check these two files: ------------------------------ logon.phtml: <? session_start(); session_register("CLIENTID"); $CLIENTID="SOMEVALUE"; header("Location: clients/editclient.phtml"); ?> ------------------------------ clients/editclient.phtml: <? session_start(); echo "CLient ID VALUE IS : $CLIENTID"; ?> When I run logon.phtml, it must create a session variable called CLIENTID and then move to the second page, which displays this variable. Each time I test this code I start a new instant of the IE and request logon.phtml (in order to create a new session), but it never works from the first time, while if I tested it a second time from the same instance of IE it works???????!!!!! Please could anyone help, why it dosn't work from the first time????? thnkx Hayan