My home Perl workspace is currently on ActiveState 5.16.3 The production server is using cPanel on VPS - and depending on the OS configuration on the server, cPanel STILL ships with Perl 5.8.8. (And I believe Plesk does the same.) What I'm writing has to work at least adequately on 5.8.8 and up because this code is going into an app that has to run on 5.8.8 and up.
The version of cPanel that ships with Perl 5.8.8 also ships with a 3rd-party install of Perl 5.14 - but the problem there is that you can't update the installed modules in the 3rd-party install. (Although I may have figured out a way to work around that annoyance - needs some testing, though, and it doesn't help other users using installing the app who are on all sorts of different servers.)
So Net::SMTPS works for this problem. Hopefully by the time it stops working, cPanel will be shipping with a more current version of Perl.