[Dovecot] SSL / TLS

[Carlos Williams]

I am running Postfix and Dovecot on my mail server. I am required now
to have SSL/TLS on my mail server. I did check and found out that I
have a SSL certificate with Verisign issued to my mail servers FQDN.
Now my question is when reading the Dovecot Wiki, I noticed it said
that it is not common to use SSL but rather TLS on most mail servers.
Even though SSL will work, which should I use on my server? We already
have a purchased SSL certificate but does that really matter? Should I
simply just revoke that certificate & use TLS instead?

So when I read this link:

http://wiki.dovecot.org/SSL/DovecotConfiguration

Is it talking about a actual SSL certificate or TLS?

Thanks for any clarification!

- Carlos