Postfix is an attempt to provide an alternative to the widely-used Sendmail program. Postfix attempts to be fast, easy to administer, and hopefully secure, while at the same time being sendmail compatible enough to not upset your users.
License: IBM Public License
Changes:
The SMTP server did not ask for a clientcertificate with "smtpd_tls_req_ccert = yes".Reduced TCP performance is avoided when reusing anSMTP connection with a larger than 4096-byte TCPMSS value.
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