Session problem

Warning: session_register() [function.session-register]: Cannot send session cache limiter - headers already sent (output started at /server/web/xx.biz/htdocs/sub/xxx/index.php:11) in /server/web/xx.biz/htdocs/sub/xxx/login.php on line 5

if (!session_is_registered("meno"))
    session_register("meno");

<?php

require_once dirname(__FILE__)."/config.php";

if (!session_is_registered("meno"))
    session_register("meno")

if (!session_is_registered("heslo"))
    session_register("heslo");
 
if (!session_is_registered("prava"))
    session_register("prava");

if (isset($_POST['submit'])) {

    $select = mysql_query("SELECT `meno`,`heslo`,`prava` FROM `uzivatelia` WHERE `meno`='".addslashes($_POST['meno'])."' AND `heslo`='".md5(trim($_POST['heslo']))."'") or die (mysql_error());
    $udaje = mysql_fetch_assoc($select);

    if (mysql_num_rows($select)==1) {
        session_regenerate_id();
        $_SESSION['meno'] = $_POST['meno'];
        $_SESSION['heslo'] = md5($_POST['heslo']);
        $_SESSION['prava'] = $udaje['prava'];
        header("Location: ./admin/index.php");
    } else {
        header("Location: ./index.php?page=prihlasenie&code=401", 401);
    }
   
}

if (isset($_GET['logout'])) {
    unset($_SESSION['meno']);
    unset($_SESSION['heslo']);
    unset($_SESSION['prava']);
    session_destroy();
}

isset($_GET['code']) && $_GET['code']=="401" ?
   $title = "<h1>Neautorizovaný prístup (Chyba 401)</h1>" :
   $title = "<h1>Prihlásenie</h1";
?>