+#define PDKIM_OVERSIGN_HEADERS "+From:+Sender:+Reply-To:+Subject:+Date:"\
+ "+Message-ID:+To:+Cc:+MIME-Version:+Content-Type:"\
+ "+Content-Transfer-Encoding:+Content-ID:"\
+ "+Content-Description:+Resent-Date:+Resent-From:"\
+ "+Resent-Sender:+Resent-To:+Resent-Cc:"\
+ "+Resent-Message-ID:+In-Reply-To:+References:"\
+ "+List-Id:+List-Help:+List-Unsubscribe:"\
+ "+List-Subscribe:+List-Post:+List-Owner:+List-Archive"
+