Browser compatibility issue with Login script

Hey all, new to PHPfreaks, seems like a very active site. Anyhow, I'm having an issue with this login script. It works just fine for me in chrome and safari, but in firefox and ie it does nothing, not even spit out an error. I'm not sure what's going wrong here, I'm thinking something with the header function. 

<?php 
session_start();
include 'dbcon.php';

$err = array();

foreach($_GET as $key => $value) {
	$get[$key] = filter($value); //get variables are filtered.
}

if ($_POST['doLogin']=='Login')
{

foreach($_POST as $key => $value) {
	$data[$key] = filter($value); // post variables are filtered
}


$user_email = $data['usr_email'];
$pass = $data['pwd'];


if (strpos($user_email,'@') === false) {
    $user_cond = "user_name='$user_email'";
} else {
      $user_cond = "user_email='$user_email'";
    
}

	
$result = mysql_query("SELECT `id`,`pwd`,`full_name`,`approved`,`user_level` FROM adminusers WHERE 
           $user_cond
			AND `banned` = '0'
			") or die (mysql_error()); 
$num = mysql_num_rows($result);

  // Match row found with more than 1 results  - the user is authenticated. 
    if ( $num > 0 ) { 
	
	list($id,$pwd,$full_name,$approved,$user_level) = mysql_fetch_row($result);
	
	if(!$approved) {
	//$msg = urlencode("Account not activated. Please check your email for activation code");
	$err[] = "Account not activated.";
	
	//header("Location: login.php?msg=$msg");
	 //exit();
	 }
	 
		//check against salt
	if ($pwd === PwdHash($pass,substr($pwd,0,9))) { 
	if(empty($err)){			

     // this sets session and logs user in  
       session_start();
	   session_regenerate_id (true); //prevent against session fixation attacks.

	   // this sets variables in the session 
		$_SESSION['user_id']= $id;  
		$_SESSION['user_name'] = $full_name;
		$_SESSION['user_level'] = $user_level;
		$_SESSION['HTTP_USER_AGENT'] = md5($_SERVER['HTTP_USER_AGENT']);
		
		//update the timestamp and key for cookie
		$stamp = time();
		$ckey = GenKey();
		mysql_query("update adminusers set `ctime`='$stamp', `ckey` = '$ckey' where id='$id'") or die(mysql_error());
		
		//set a cookie 
		
	   if(isset($_POST['remember'])){
				  setcookie("user_id", $_SESSION['user_id'], time()+60*60*24*COOKIE_TIME_OUT, "/");
				  setcookie("user_key", sha1($ckey), time()+60*60*24*COOKIE_TIME_OUT, "/");
				  setcookie("user_name",$_SESSION['user_name'], time()+60*60*24*COOKIE_TIME_OUT, "/");
				   }
		  header("Location: ../index.php");
		  exit ();
		 }
		}
		else
		{
		//$msg = urlencode("Invalid Login. Please try again with correct user email and password. ");
		$err[] = "Invalid Login. Please try again with correct user email and password.";
		//header("Location: login.php?msg=$msg");
		}
	} else {
		$err[] = "Error - Invalid login. No such user exists";
	  }		
}
					 
					 

?>
<script language="JavaScript" type="text/javascript" src="js/jquery-1.3.2.min.js"></script>
<script language="JavaScript" type="text/javascript" src="js/jquery.validate.js"></script>
<script>
  $(document).ready(function(){
    $("#logForm").validate();
  });
</script>