CodeIgniter: SSL/TLS SMTP Auth Email from PHPMailer Code

I'm trying to use the CodeIgniter Email Class to write a secure SMTP email; either SSL or TLS (preferred). In the past, I've successfully used PHPMailer with Secure Auth and TLS. I believe it was a secure connection. TLS shows up in the email header.

Does CodeIngiters' Email Class support secure SMTP authentication with TLS?

Note, this is not a Gmail question. I'm trying to use it with an MS Exchange Server. I've confirmed the PHPMailer code below functions correctly.

include_once('includes/class.phpmailer.php');
$mail = new PHPMailer(true);
$mail->IsSMTP();
$mail->Host = 'www.domain.com';

$mail->SMTPAuth = true;
$mail->SMTPSecure = "tls";
$mail->Port     = '25';
$mail->Timeout  = '60';

$mail->Username = 'user@domain.com';
$mail->Password = 'password';

$mail->From     = 'alerts@domain.com';
$mail->FromName = 'Alerts';

$mail->Subject  = 'Test from test email file.';
$mail->IsHTML(true);
$mail->MsgHTML('This is just a test.');

// To
$mail->AddAddress('alerts@domain.com', 'Research');
$result = $mail->Send();

With CodeIgniter I've already extended the Email Class (MY_Email.php). The class is a bit big to post here. But, here's the error I keep getting.

Settings:

array(7) { 
["smtp_host"]=> string(26) "tls://www.domain.com" 
["smtp_port"]=> string(2) "25" 
["smtp_user"]=> string(17) "alerts@domain.com" 
["smtp_pass"]=> string(9) "password" 
["smtp_to_email"]=> string(26) "user@domain.com" 
["smtp_from_email"]=> string(26) "user@domain.com" 
["smtp_from_name"]=> string(24) "Test from Application" 
}

Error Message:

fsockopen(): SSL operation failed with code 1. OpenSSL Error messages: error:1408F10B:SSL routines:func(143):reason(267)

Any idea what reason 267 is?