Thanks, I'll look at those references.
I have sendmail, but I put postfix behind it and finally pop-before-smtp
The idea there was to be able to relay mail from anywhere to anywhere, for users only. It works great but the passwords and data are transmitted without encryption, which is not good.
So I did just check out stunnel, and it works great. I tried it with imapd.
No problem there, I think maybe I will try it with pop3s and see if I can use pop-before-smtp.
What I really need is smtp that will allow only valid user incoming mail from anyone, but also relay for valid users.
If stunnel will work with my current setup, I think it will have it covered.