session_register() ไม่ทำงานบน php5 session_register() ไม่ทำงานบน php5 พอจะรูวิธีใช้ป่าวครับผลอง

<?
session_start();
$sess_userid=$_SESSION[sess_userid];
$sess_username=$_SESSION[sess_username];
if ($sess_userid<>session_id() or $sess_username=="") {
	header( "Location: login.php"); exit();
} 
?>
<?

$id_color=$_GET["id_color"];

include "connect.php";
$sql="select count_click1 from tb_color where id_color='$id_color' ";
$result=mysql_db_query($dbname,$sql);
$rs=mysql_fetch_array($result);
$count_click1=$rs[count_click1];

$count=$count_click1+1;

$sql2="update tb_color set count_click1='$count' where id_color='$id_color' ";
$result2=mysql_db_query($dbname,$sql2);

session_register("sess_id");
session_register("sess_photo_color");
session_register("sess_bar");
session_register("sess_name");
session_register("sess_weight");
session_register("sess_price");
session_register("sess_num");

if (count($sess_id)=="0") {
	$check=1;
} else  if (!in_array($id_color, $sess_id)) {
	$check=1;
}

if ($check==1) {
	include "connect.php";
	$sql="select * from tb_color where id_color='$id_color' ";
	$result=mysql_db_query($dbname,$sql);
	$rs=mysql_fetch_array($result);

	$sess_id[]=$rs[id_color];
	$sess_photo_color[]=$rs[photo_color];
    $sess_bar[]=$rs[bar_color];
	$sess_name[]=$rs[name_color];
	$sess_weight[]=$rs[weight_color];
	$sess_price[]=$rs[price_color];
	$sess_num[]=1;

}
header('Location: order-product.php');
?>