--- sendmail-8.17.1/cf/m4/proto.m4	2021-07-14 07:34:51.000000000 +0000
+++ sendmail-8.17.1/cf/m4/proto.m4.new	2022-02-01 09:57:37.391956480 +0000
@@ -6,6 +6,9 @@
 # Copyright (c) 1988, 1993
 #	The Regents of the University of California.  All rights reserved.
 #
+# Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
+# Use is subject to license terms.
+#
 # By using this file, you agree to the terms and conditions set
 # forth in the LICENSE file which can be found at the top level of
 # the sendmail distribution.
@@ -16,7 +19,7 @@
 VERSIONID(`$Id: proto.m4,v 8.762 2013-11-22 20:51:13 ca Exp $')
 
 # level CF_LEVEL config file format
-V`'CF_LEVEL`'ifdef(`NO_VENDOR',`', `/ifdef(`VENDOR_NAME', `VENDOR_NAME', `Berkeley')')
+V`'CF_LEVEL`'ifdef(`NO_VENDOR',`', `/ifdef(`VENDOR_NAME', `VENDOR_NAME', `Sun')')
 divert(-1)
 
 dnl if MAILER(`local') not defined: do it ourself; be nice
@@ -616,7 +619,7 @@
 _OPTION(ControlSocketName, `confCONTROL_SOCKET_NAME', `/var/spool/mqueue/.control')
 
 # Maximum MIME header length to protect MUAs
-_OPTION(MaxMimeHeaderLength, `confMAX_MIME_HEADER_LENGTH', `0/0')
+_OPTION(MaxMimeHeaderLength, `confMAX_MIME_HEADER_LENGTH', `2048/1024')
 
 # Maximum length of the sum of all headers
 _OPTION(MaxHeadersLength, `confMAX_HEADERS_LENGTH', `32768')