--- /dev/null
+/*************************************************
+* Exim - an Internet mail transport agent *
+*************************************************/
+
+/* Copyright (c) University of Cambridge 1995 - 2013 */
+/* See the file NOTICE for conditions of use and distribution. */
+
+/* This file (will) provide DANE support for Exim using the GnuTLS library,
+but is not yet an available supported implementation. This file is #included
+into dane.c when USE_GNUTLS has been set. */
+
+/* As of March 2014, the reference implementation for DANE that we are
+using was written by Viktor Dukhovny and it supports OpenSSL only. At
+some point we will add GnuTLS support, but for right now just abort the
+build and explain why. */
+
+
+#error No support for DANE using GnuTLS yet.
+
+
+/* End of dane-gnu.c */