vt7 dev release - class.phpmailer.php is ~6 years old...

from github:

Commits on Apr 11, 2013 5.2.6 release

I recently installed the most recent version (5.2.22) on a customer's vtiger 5.4.0 system because the old one will not connect to certain tls smtp servers. The only thing I had to do was to include the class.smtp.php at the top of the class.phpmailer.php file to get it to work.

Please update this library.