+PH/40 The value set for $authenticated_id in an authenticator may not contain
+ binary zeroes or newlines because the value is written to log lines and
+ to spool files. There was no check on this. Now the value is run through
+ the string_printing() function so that such characters are converted to
+ printable escape sequences.
+
+PH/41 $message_linecount is a new variable that contains the total number of
+ lines in the message. Compare $body_linecount, which is the count for the
+ body only.
+