There is a new mail server option that will add a new later of encryption to the authenication process.  You will not know if you need this option unless your server complains with needing a different authenication type.  As an example error you may see...

SMTP: No supported authentication methods (code: 250, response: PIPELINING SIZE 10240000 ETRN AUTH DIGEST-MD5 CRAM-MD5 ENHANCEDSTATUSCODES 8BITMIME DSN )

Just for your information rmoov now supports "DIGEST-MD5" as the extra encryption.