+## DKIM headers list.
+DEFCONF(dkim_headers, m4_dnl
+References : In-Reply-To : Subject : To : Date : Message-ID : m4_dnl
+From : Sender : Reply-To : Cc : m4_dnl
+Resent-Date : Resent-From : Resent-Sender : Resent-To : Resent-Cc : m4_dnl
+Resent-Message-ID : m4_dnl
+Content-Transfer-Encoding : Content-Type : MIME-Version : m4_dnl
+Content-ID : Content-Description : m4_dnl
+List-Id : List-Help : List-Unsubscribe : List-Subscribe : m4_dnl
+List-Post : List-Owner : List-Archive m4_dnl
+)
+