Login form without reloading

Login form without reloading

Hello everyone,
I have little a problem with set up my login form with jQuery functions. My login form is in PHP of course, it's very simple, it has only one input to write proper password - after that user can see "hide section". I want to use jQuery to make this form free of any reloading, for example when user puts wrong password.
Ok, here is my script, I have just set up in jQuery "error message" with fade effect, but after submit button page is reloading (and that is what I can't do it). How to make it with no reloading?

  1. <?php
    $LOGIN_INFORMATION = array('my_pass');

    define('USE_USERNAME', false);
    define('LOGOUT_URL', '');
    define('TIMEOUT_MINUTES', 10);
    define('TIMEOUT_CHECK_ACTIVITY', true);

    $timeout = (TIMEOUT_MINUTES == 0 ? 0 : time() + TIMEOUT_MINUTES * 60);

    if(isset($_GET['logout'])) {
      setcookie("verify", '', $timeout, '/');
      header('Location: ' . LOGOUT_URL);
      exit();
    }

    if(!function_exists('showLoginPasswordProtect')) {
    function showLoginPasswordProtect($error_msg) {
    ?>




















    <script type="text/javascript" src="jquery.js"></script>
    <script>
    $(function() {

    $('.error').hide();
    $(".error").fadeIn(2000);

    return false;
    });

    </script>

    <form method="post">
    <?php echo $error_msg.'<br /><br />' ?>
    <?php if (USE_USERNAME) echo 'Login:<br /><input type="input" name="access_login" /><br />Password<br />'; ?>
    <input type="password" name="access_password" />
    <br /><br />
    <input type="submit" name="Submit" value="Submit" />
    </form>




















    <?php
      die();
    }
    }

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

      $login = isset($_POST['access_login']) ? $_POST['access_login'] : '';
      $pass = $_POST['access_password'];
      if (!USE_USERNAME && !in_array($pass, $LOGIN_INFORMATION)
      || (USE_USERNAME && ( !array_key_exists($login, $LOGIN_INFORMATION) || $LOGIN_INFORMATION[$login] != $pass ) )
      ) {
        showLoginPasswordProtect("<font style='color: #333' class='error'>Incorrect password</font>");
      }
      else {

        setcookie("verify", md5($login.'%'.$pass), $timeout, '/');

        unset($_POST['access_login']);
        unset($_POST['access_password']);
        unset($_POST['Submit']);
      }

    }

    else {

      if (!isset($_COOKIE['verify'])) {
        showLoginPasswordProtect("");
      }

      $found = false;
      foreach($LOGIN_INFORMATION as $key=>$val) {
        $lp = (USE_USERNAME ? $key : '') .'%'.$val;
        if ($_COOKIE['verify'] == md5($lp)) {
          $found = true;
          if (TIMEOUT_CHECK_ACTIVITY) {
            setcookie("verify", md5($lp), $timeout, '/');
          }
          break;
        }
      }
      if (!$found) {
        showLoginPasswordProtect("");
      }

    }

    ?>