Hey Alex,
That is a pretty large request =) I don't know that much about SSL other than installing a certificate on a webserver, but some quick searching, found there are multiple ways to encrypt a message, OpenSSL, PGP, and others. i am not sure which one would work for all situations or which is the best. Any ideas on what is most commonly used? I found this article on Zends site that talks about PGP.
<http://devzone.zend.com/node/view/id/1265#Heading5>
if you look at the stuff i just added, it does base64encoding, so theoretically you could use there shell_exec function to launch gpg and encrypt the message stuff.
Should it use a built-in php function as a requirement? php.net has some info on encrypting/decrypting/signing messages in their OpenSSL stuff.
All the PGP stuff with PHP seems to require command line or extra utilities, which goes against the QCodo not using outside packages.
if you can point me to some documentation or example code on how to implement it that would be cross system compatible and work for all of the major email clients i will look at it.
I am pretty swamped right now, and email attachments was a need I had, so I added it while working on that. I don't have a need for SSL right now, so it probably wont be high priority, but i am pretty familiar with the QEmailServer code right now, so if you find something that wouldn't be too much extra work, I would take a look.
I would think that QEmailServer, would need to accept a private key to encrypt the message with and it would need a special port to talk with.
sorry i couldn't be much more help. if you find more info let me know.