+JH/05 Have the EHLO response advertise VRFY, if there is a vrfy ACL defined.
+ Previously we did not; the RFC seems ambiguous and VRFY is not listed
+ by IANA as a service extension. However, John Klensin suggests that we
+ should.
+
+JH/06 Bug 2017: Fix DKIM verification in -bh test mode. The data feed into
+ the dkim code may be unix-mode line endings rather than smtp wire-format
+ CRLF, so prepend a CR to any bare LF.
+
+JH/07 Rationalise the coding for callout smtp conversations and transport ones.
+ As a side-benfit, callouts can now use PIPELINING hence fewer round-trips.
+
+JH/08 Bug 2016: Fix DKIM verification vs. CHUNKING. Any BDAT commands after
+ the first were themselves being wrongly included in the feed into dkim
+ processing; with most chunk sizes in use this resulted in an incorrect
+ body hash calculated value.
+
+JH/09 Bug 2014: permit inclusion of a DKIM-Signature header in a received
+ DKIM signature block, for verification. Although advised against by
+ standards it is specifically not ruled illegal.
+
+JH/10 Bug 2025: Fix reception of (quoted) local-parts with embedded spaces.
+
+JH/11 Bug 2029: Fix crash in DKIM verification when a message signature block is
+ missing a body hash (the bh= tag).
+
+JH/12 Bug 2018: Re-order Proxy Protocol startup versus TLS-on-connect startup.
+ It seems that HAProxy sends the Proxy Protocol information in clear and
+ only then does a TLS startup, so do the same.
+
+JH/13 Bug 2027: Avoid attempting to use TCP Fast Open for non-transport client
+ TCP connections (such as for Spamd) unless the daemon successfully set
+ Fast Open mode on its listening sockets. This fixes breakage seen on
+ too-old kernels or those not configured for Fast Open, at the cost of
+ requiring both directions being enabled for TFO, and TFO never being used
+ by non-daemon-related Exim processes.
+
+JH/14 Bug 2000: Reject messages recieved with CHUNKING but with malformed line
+ endings, at least on the first header line. Try to canonify any that get
+ past that check, despite the cost.
+
+JH/15 Angle-bracket nesting (an error inserted by broken sendmails) levels are
+ now limited to an arbitrary five deep, while parsing addresses with the
+ strip_excess_angle_brackets option enabled.
+
+PP/03 Bug 2018: For Proxy Protocol and TLS-on-connect, do not over-read and
+ instead leave the unprompted TLS handshake in socket buffer for the
+ TLS library to consume.
+
+PP/04 Bug 2018: Also handle Proxy Protocol v2 safely.
+
+PP/05 FreeBSD compat: handle that Ports no longer create /usr/bin/perl
+
+JH/16 Drop variables when they go out of scope. Memory management drops a whole
+ region in one operation, for speed, and this leaves assigned pointers
+ dangling. Add checks run only under the testsuite which checks all
+ variables at a store-reset and panics on a dangling pointer; add code
+ explicitly nulling out all the variables discovered. Fixes one known
+ bug: a transport crash, where a dangling pointer for $sending_ip_address
+ originally assigned in a verify callout, is re-used.
+
+PP/06 Drop '.' from @INC in various Perl scripts.
+
+PP/07 Switch FreeBSD iconv to always use the base-system libc functions.
+
+PP/08 Reduce a number of compilation warnings under clang; building with
+ CC=clang CFLAGS+=-Wno-dangling-else -Wno-logical-op-parentheses
+ should be warning-free.
+
+JH/17 Fix inbound CHUNKING when DKIM disabled at runtime.
+
+HS/01 Fix portability problems introduced by PP/08 for platforms where
+ realloc(NULL) is not equivalent to malloc() [SunOS et al].
+
+HS/02 Bug 1974: Fix missing line terminator on the last received BDAT
+ chunk. This allows us to accept broken chunked messages. We need a more
+ general solution here.
+
+PP/09 Wrote util/chunking_fixqueue_finalnewlines.pl to help recover
+ already-broken messages in the queue.
+
+JH/18 Bug 2061: Fix ${extract } corrupting an enclosing ${reduce } $value.
+