add PFS to postfix
requieres postfix > 2.6 and openssl > 0.9
openssl gendh -out /etc/postfix/dh_512.pem -2 512 openssl gendh -out /etc/postfix/dh_2048.pem -2 2048
postconf -e "smtpd_tls_dh1024_param_file = /etc/postfix/dh_2048.pem" postconf -e "smtpd_tls_dh512_param_file = /etc/postfix/dh_512.pem" postconf -e "smtpd_tls_eecdh_grade = strong" postconf -e "tls_preempt_cipherlist = yes" postconf -e "smtpd_tls_loglevel = 1" postconf -e "smtp_tls_loglevel = 1"