diff --git a/lib/mu-msg-sexp.c b/lib/mu-msg-sexp.c
index cf5f5be8..e4981241 100644
--- a/lib/mu-msg-sexp.c
+++ b/lib/mu-msg-sexp.c
@@ -46,9 +46,6 @@ append_sexp_attr_list (GString *gstr, const char* elm, const GSList *lst)
 	g_string_append (gstr, ")\n");
 }
 
-
-
-
 static void
 append_sexp_attr (GString *gstr, const char* elm, const char *str)
 {
@@ -71,7 +68,6 @@ append_sexp_attr (GString *gstr, const char* elm, const char *str)
 	g_free (esc);
 }
 
-
 static void
 append_sexp_body_attr (GString *gstr, const char* elm, const char *str)
 {
@@ -86,11 +82,6 @@ append_sexp_body_attr (GString *gstr, const char* elm, const char *str)
 	g_free (esc);
 }
 
-
-
-
-
-
 struct _ContactData {
 	gboolean from, to, cc, bcc, reply_to;
 	GString *gstr;
@@ -118,6 +109,7 @@ get_name_addr_pair (MuMsgContact *c)
 	return pair;
 }
 
+
 static void
 add_prefix_maybe (GString *gstr, gboolean *field, const char *prefix)
 {
@@ -172,6 +164,36 @@ each_contact (MuMsgContact *c, ContactData *cdata)
 }
 
 
+static void
+maybe_append_list_post_as_reply_to (GString *gstr, MuMsg *msg)
+{
+	/* some mailing lists do not set the reply-to; see pull #1278. So for
+	 * those cases, check the List-Post address and use that instead */
+
+	GMatchInfo	*minfo;
+	GRegex		*rx;
+	const char*	 list_post;
+
+	list_post = mu_msg_get_header (msg, "List-Post");
+	if (!list_post)
+		return;
+
+	rx = g_regex_new ("^(<?mailto:)?([a-z0-9%+@.-]+)>?", G_REGEX_CASELESS, 0, NULL);
+	g_return_if_fail(rx);
+
+	if (g_regex_match (rx, list_post, 0, &minfo)) {
+		char	*addr;
+		addr = g_match_info_fetch (minfo, 2);
+		g_string_append_printf (gstr,"\t:reply-to ((nil . \"%s\"))\n", addr);
+		g_free(addr);
+	}
+
+	g_match_info_free (minfo);
+	g_regex_unref (rx);
+}
+
+
+
 static void
 append_sexp_contacts (GString *gstr, MuMsg *msg)
 {
@@ -184,9 +206,11 @@ append_sexp_contacts (GString *gstr, MuMsg *msg)
 
 	mu_msg_contact_foreach (msg, (MuMsgContactForeachFunc)each_contact,
 				&cdata);
-
 	if (cdata.from || cdata.to || cdata.cc || cdata.bcc || cdata.reply_to)
 		gstr = g_string_append (gstr, ")\n");
+
+	if (!cdata.reply_to)
+		maybe_append_list_post_as_reply_to (gstr, msg);
 }
 
 struct _FlagData {
@@ -557,7 +581,6 @@ append_sexp_tags (GString *gstr, MuMsg *msg)
 	g_string_free (tagstr, TRUE);
 }
 
-
 char*
 mu_msg_to_sexp (MuMsg *msg, unsigned docid, const MuMsgIterThreadInfo *ti,
 		MuMsgOptions opts)
@@ -580,9 +603,8 @@ mu_msg_to_sexp (MuMsg *msg, unsigned docid, const MuMsgIterThreadInfo *ti,
 
 	append_sexp_attr (gstr, "subject", mu_msg_get_subject (msg));
 
-	/* in the no-headers-only case (see below) we get a more
-	 * complete list of contacts, so no need to get them here if
-	 * that's the case */
+	/* in the no-headers-only case (see below) we get a more complete list
+	 * of contacts, so no need to get them here if that's the case */
 	if (opts & MU_MSG_OPTION_HEADERS_ONLY)
 		append_sexp_contacts (gstr, msg);