Thanks for the clarification.

But in my case, sending mail is usually a requirement that requires little beyond sending an HTML and/or text mail with some files attached, and that is well implemented by MIME::Lite.

Exactly - my requirements in this case are much the same without a need for attachments. I have a module written that is working elsewhere without issue that I can simply drop in to the new project. The question was never about the Perl module...it was about recommendations for an MTA that will work with Perl.

...and the scripts also only talk to my MTA...

What MTA do you use Corion?