Well security is a ongoing adventure actually. However both
Exim and Postfix have good reputations.
does exim have the security reputation (in the real world) that qmail
/* Security is a work in progress - dreamwvr */
# Note: To begin Journey type man afterboot,man help,man hier[.]
// "Who's Afraid of Schrodinger's Cat?" /var/(.)?mail/me \? ;-]