Hello,
We've added client side encryption support with PGP in the webmail. You can find this in the settings of the webmail and, you can generate / import keys with the button at the top of the compose window. Private keys and passwords are never transmitted to the server, they are stored in the html5 local storage of your browser.
Best regards, Pierre Barre ¿cuáles son sus apreciaciones? Saludos.