- Postfix no longer automatically appends the system default CA
(certificate authority) certificates, when it reads the CA
certificates specified with {smtp, lmtp, smtpd}_tls_CAfile or
with {smtp, lmtp, smtpd}_tls_CApath. This prevents third-party
certificates from getting mail relay permission with the
permit_tls_all_clientcerts feature. Unfortunately, this change
may cause compatibility problems with configurations that rely
on certificate verification for other purposes. To get the old
behavior, specify "tls_append_default_CA = yes".
- A prior fix for compatibility with Postfix < 2.3 was incomplete.
When pipe-to-command delivery fails with a signal, mail is now
correctly deferred, instead of being returned to sender.
- Poor smtpd_proxy_filter TCP performance over loopback (127.0.0.1)
connections was fixed by adapting the output buffer size to the MTU.
- The SMTP server no longer applies the reject_rhsbl_helo feature
to non-domain forms such as network addresses. This would cause
false positives with dbl.spamhaus.org.
- The Postfix SMTP server failed to deliver a "421" response and
hang up the connection after Milter error. Instead, the server
delivered a "503 Access denied" response and left the connection
open, due to some Postfix 1.1 workaround for RFC 2821.
- The milter_header_checks parser failed to enable any of the actions
that have no effect on message delivery (warn, replace, prepend,
ignore, dunno, and ok).
d7ff5b165b