Problem Using Mail Queue

Hi I'm tring to Use the Mail Queue System, and I have make every step to follow:

1.- I have created a table in My DB
2.- I have changed my include path

I put the example code on a page:

<?php
include './config.php';
include_once 'Mail/Queue.php';

/* we use the db_options and mail_options here */
$mail_queue =& new Mail_Queue($container_options, $mail_options);

$from = 'user@server.com';
$from_name = 'admin';
$recipient = 'farith@carreraenlinea.com';
$recipient_name = 'recipient';
$message = 'Test message';
$from_params = empty($from_name) ? '<'.$from.'>' : '"'.$from_name.'" <'.$from.'>';
$recipient_params = empty($recipient_name) ? '<'.$recipient.'>' : '"'.$recipient_name.'" <'.$recipient.'>';
$hdrs = array(
'From' => $from_params,
'To' => $recipient_params,
'Subject' => 'test message body',
);
$mime =& new Mail_mime();
$mime->setTXTBody($message);
$body = $mime->get();
$hdrs = $mime->headers($hdrs);

// Put message to queue
$mail_queue->put($from, $recipient, $hdrs, $body);

// Also you could put this msg in more advanced mode
$seconds_to_send = 3600;
$delete_after_send = false;
$id_user = 7;
$mail_queue->put( $from, $recipient, $hdrs, $body, $seconds_to_send, $delete_after_send, $id_user );

// TO SEND EMAILS IN THE QUEUE

// How many mails could we send each time
$max_ammount_mails = 50;
$mail_queue =& new Mail_Queue($container_options, $mail_options);
$mail_queue->sendMailsInQueue($max_ammount_mails);

?>





AND I GET THIS ERROR

Fatal error: Call to a member function on a non-object in .:.:..:.:/PEAR/Mail/Queue/Container/db.php on line 189


Can someone Helpme with This??

I get the error on this line:

$mail_queue->put($from, $recipient, $hdrs, $body);

$container_options = array(
'type' => 'mdb'
.
.
.
.
);


I just change de type form db to mdb on the include