Problemer med setcookie()

Kode 

<?php
	$host = "localhost";
	$user = "*******";
	$password = "*******";
	$database = "*******";
	
	$connection = mysql_connect($host,$user,$password) or die(mysql_error());
	mysql_select_db($database) or die(mysql_error());
	
	if(isset($_POST['Submit'])){
	$sql = "SELECT * FROM users WHERE username='$_POST[username]'";
	$result = mysql_query($sql,$connection) or die(mysql_error());
	while($row = mysql_fetch_array($result)){
		$password = $row[password];
		$username = $row[username];
	}
		$user_password = $_POST['password']; 
		if($password == $user_password){
		setcookie(login, $username, time()+2592000, "/");
		$msg[ok] = "Du er nu logget ind!";
		}
		else{
		$msg[ok] = "Forkert password!";	
		}
	}
	
	if(empty($_COOKIE['login'])){
		$bruger = "
		<table width='130' class='bodytable' id='sidemenu'><tr><th>Login</th></tr>
		<tr><td>
		<form id='login' name='login' method='post' action='$_SERVER[PHP_SELF]'>
      <label>Brugernavn<br />
<input name='username' type='text' size='10' />
      </label>
      <br />
      <label>Password<br />
<input name='password' type='password' size='10' />
      </label>
      <label>
        <br />
        <input type='submit' name='Submit' value='Login' />
      </label>
    </form>
	</td></tr></table>";
	}	
	print $bruger;
	?>