+JH/41 Fix the loop reading a message header line to check for integer overflow,
+ and more-often against header_maxsize. Previously a crafted message could
+ induce a crash of the recive process; now the message is cleanly rejected.
+
+JH/42 Bug 2366: Fix the behaviour of the dkim_verify_signers option. It had
+ been totally disabled for all of 4.91. Discovery and fix by "Mad Alex".
+