leaving it open for efficiency as that will be quickly detected by the
check on the next write.
+HS/01 Bug 1671: Fix post transport crash.
+ Processing the wait-<transport> messages could crash the delivery
+ process if the message IDs didn't exist for some reason. When
+ using 'split_spool_directory=yes' the construction of the spool
+ file name failed already, exposing the same netto behaviour.
+
+JH/03 Bug 425: Capture substrings in $regex1, $regex2 etc from regex &
+ mime_regex ACL conditions.
+
+JH/04 Bug 1686: When compiled with EXPERIMENTAL_DSN_INFO: Add extra information
+ to DSN fail messages (bounces): remote IP, remote greeting, remote response
+ to HELO, local diagnostic string.
+
+JH/05 Downgrade message for a TLS-certificate-based authentication fail from
+ log line to debug. Even when configured with a tls authenticator many
+ client connections are expected to not authenticate in this way, so
+ an authenticate fail is not an error.
+
+HS/02 Add the Exim version string to the process info. This way exiwhat
+ gives some more detail about the running daemon.
+
+JH/06 Bug 1395: time-limit cacheing of DNS lookups, to the TTL value. This may
+ matter for fast-change records such as DNSBLs.
+
+JH/07 Bug 1678: Always record an interface option value, if set, as part of a
+ retry record, even if constant. There may be multiple transports with
+ different interface settings and the retry behaviour needs to be kept
+ distinct.
+
+JH/08 Bug 1586: exiqgrep now refuses to run if there are unexpected arguments.
+
+JH/09 Bug 1700: ignore space & tab embedded in base64 during decode.
+
+JH/10 Bug 840: fix log_defer_output option of pipe transport
+
+JH/11 Bug 830: use same host for all RCPTS of a message, even under
+ hosts_randomize. This matters a lot when combined with mua_wrapper.
+
+JH/12 Bug 1706: percent and underbar characters are no longer escaped by the
+ ${quote_pgsql:<string>} operator.
+
+JH/13 Bug 1708: avoid misaligned access in cached lookup.
+
+JH/14 Change header file name for freeradius-client. Relevant if compiling
+ with Radius support; from the Gentoo tree and checked under Fedora.
+
+JH/15 Bug 1712: Introduce $prdr_requested flag variable
+
+JH/16 Bug 1714: Permit an empty string as expansion result for transport
+ option transport_filter, meaning no filtering.
+
+JH/17 Bug 1713: Fix non-PDKIM_DEBUG build. Patch from Jasen Betts.
+
+JH/18 Bug 1709: When built with TLS support, the tls_advertise_hosts option now
+ defaults to "*" (all hosts). The variable is now available when not built
+ with TLS, default unset, mainly to enable keeping the testuite sane.
+ If a server certificate is not supplied (via tls_certificate) an error is
+ logged, and clients will find TLS connections fail on startup. Presumably
+ they will retry in-clear.
+ Packagers of Exim are strongly encouraged to create a server certificate
+ at installation time.
+
+HS/03 Add -bP config_file as a synonym for -bP configure_file, for consistency
+ with the $config_file variable.
+
+JH/19 Two additional event types: msg:rcpt:defer and msg:rcpt:host:defer. Both
+ in transport context, after the attempt, and per-recipient. The latter type
+ is per host attempted. The event data is the error message, and the errno
+ information encodes the lookup type (A vs. MX) used for the (first) host,
+ and the trailing two digits of the smtp 4xx reponse.
+
+GF/01 Bug 1715: Fix for race condition in exicyclog, where exim could attempt
+ to write to mainlog (or rejectlog, paniclog) in the window between file
+ creation and permissions/ownership being changed. Particularly affects
+ installations where exicyclog is run as root, rather than exim user;
+ result is that the running daemon panics and dies.
+
+JH/20 Bug 1701: For MySQL lookups, support MySQL config file option group names.
+
+JH/21 Bug 1720: Add support for priority groups and weighted-random proxy
+ selection for the EXPERIMENTAL_SOCKS feature, via new per-proxy options
+ "pri" and "weight". Note that the previous implicit priority given by the
+ list order is no longer honoured.
+
+JH/22 Bugs 963, 1721: Fix some corner cases in message body canonicalisation
+ for DKIM processing.
+
+JH/23 Move SOCKS5 support from Experimental to mainline, enabled for a build
+ by defining SUPPORT_SOCKS.
+
+JH/26 Move PROXY support from Experimental to mainline, enabled for a build
+ by defining SUPPORT_PROXY. Note that the proxy_required_hosts option
+ is renamed to hosts_proxy, and the proxy_{host,target}_{address,port}.
+ variables are renamed to proxy_{local,external}_{address,port}.
+
+JH/27 Move Internationalisation support from Experimental to mainline, enabled
+ for a build by defining SUPPORT_I18N
+
+JH/28 Bug 1745: Fix redis lookups to handle (quoted) spaces embedded in parts
+ of the query string, and make ${quote_redis:} do that quoting.
+
+JH/29 Move Events support from Experimental to mainline, enabled by default
+ and removable for a build by defining DISABLE_EVENT.
+
+JH/30 Updated DANE implementation code to current from Viktor Dukhovni.
+
+JH/31 Fix bug with hosts_connection_nolog and named-lists which were wrongly
+ cached by the daemon.
+
+JH/32 Move Redis support from Experimental to mainline, enabled for a build
+ by defining LOOKUP_REDIS. The libhiredis library is required.
+
+JH/33 Bug 1748: Permit ACL dnslists= condition in non-smtp ACLs if explicit
+ keys are given for lookup.
+
+JH/34 Bug 1192: replace the embedded copy of PolarSSL RSA routines in the DKIM
+ support, by using OpenSSL or GnuTLS library ones. This means DKIM is
+ only supported when built with TLS support.
+
+JH/35 Require SINGLE_DH_USE by default in OpenSSL (main config option
+ openssl_options), for security. OpenSSL forces this from version 1.1.0
+ server-side so match that on older versions.
+
Exim version 4.86
-----------------