Only one works

Hi, I am having a problem with one of my session variables, no matter what I try I can't get a second one to register. My webpage calls this script directly and I am using the webpage form variables for the variables in this script. I can register the Name variable but not the LoginName variable. What am I doing wrong?? Here is complete script: <? require_once ( "DBFunctions.php" ); #Make DB Connection $result = makeconnection(); if( $result ) {

       #validate the user
             $Name = validuser("$LoginName", "$PWord");

       if( strlen($Name) > 0 )
       {
           #start a session and register the user and limit the session to one hour
           #session_cache_expire(60);
           session_start();
           #here is where I check for registered sessions and registered users
           if(! session_is_registered("Name"))  // this works as expected
           {
                session_register("Name");
           }

           if(! session_is_registered("LoginName"))
           {
               session_register( "LoginName" );  // this does not work.
           }

           header("Location: http://www.xxxxxxxxxx.com/xxxxxxx/xxxxxxxx.php");
       }
       else
       {
           header("Location: http://www.xxxxxxxx.com/xxxxxxxx/");
           exit();
       }

} else {

       #session_unset();
       session_destroy();
       echo "Problem with database.";
       exit();

} ?>