No popup for Personal Message SMF

I have a site with Joomla 1.0.12, SMF 1.1.2 and Joomla-SMF 2.0.2

I have selected SMF as Personal Message System.

The problem is that when user marks "Show a popup when you receive new messages?" in Personal Message Options no popup appears (popup blocker disabled in web browser of course).

Does it work properly with the bridge?

I am aware the bridge modify the login code so perhaps some session variables are not set properly.

My configuration is:

Register system: Joomla/Mambo
Validation Module: Joomla/Mambo
Personal Message System: SMF

Thanks in advance.

Regards,
Pablo.

Original code related to this is in Sources/Subs.php

Code:

// Personal message popup...
if ($user_info['unread_messages'] > (isset($_SESSION['unread_messages']) ? $_SESSION['unread_messages'] : 0))
$context['user']['popup_messages'] = true;
else
$context['user']['popup_messages'] = false;
$_SESSION['unread_messages'] = $user_info['unread_messages'];

Code:

// This is done to make it easier to add to all themes...
if ($context['user']['popup_messages'] && !empty($options['popup_messages']) && (!isset($_REQUEST['action']) || $_REQUEST['action'] != 'pm'))
{
$context['html_headers'] .= '
<script language="JavaScript" type="text/javascript"><![CDATA[
if (confirm("' . $txt['show_personal_messages'] . '"))
window.open("' . $scripturl . '?action=pm");
// ]]></script>';
}