+PP/18 OpenSSL made graceful with empty tls_verify_certificates setting.
+ This is now consistent with GnuTLS, and is now documented: the
+ previous undocumented portable approach to treating the option as
+ unset was to force an expansion failure. That still works, and
+ an empty string is now equivalent.
+
+PP/19 Renamed DNSSEC-enabling option to "dns_dnssec_ok", to make it
+ clearer that Exim is using the DO (DNSSEC OK) EDNS0 resolver flag,
+ not performing validation itself.
+
+PP/20 Added force_command boolean option to pipe transport.
+ Patch from Nick Koston, of cPanel Inc.
+
+JH/15 AUTH support on callouts (and hence cutthrough-deliveries).
+ Bugzilla 321, 823.
+
+PP/21 Fix eximon continuous updating with timestamped log-files.
+ Broken in a format-string cleanup in 4.80, missed when I repaired the
+ other false fix of the same issue.
+ Report and fix from Heiko Schlichting.
+ Bugzilla 1363.
+
+PP/22 Guard LDAP TLS usage against Solaris LDAP variant.
+ Report from Prashanth Katuri.
+
+PP/23 Support safari_ecdhe_ecdsa_bug for openssl_options.
+ It's SecureTransport, so affects any MacOS clients which use the
+ system-integrated TLS libraries, including email clients.
+