I'm unable to complete the configuration for any e-mail client using SSL authentication for the domain whitephoenix.tk.
I'm able to use normally my e-mails with "Webmail: Roundcube".
Nevermind, i have found the solution by myself: i had to issue a new SSL Certificate for the domain whitephoenix.tk and include the following subdomains: mail.whitephoenix.tk; smtp.whitephoenix.tk; pop.whitephoenix.tk.