diff --git a/addons/mail/static/src/js/mail.js b/addons/mail/static/src/js/mail.js
index 5c64e49c03c..fecaa24f984 100644
--- a/addons/mail/static/src/js/mail.js
+++ b/addons/mail/static/src/js/mail.js
@@ -488,7 +488,7 @@ var ThreadComposeMessage = MessageCommon.extend({
         // have unknown names -> call message_get_partner_info_from_emails to try to find partner_id
         var find_done = $.Deferred();
         if (names_to_find.length > 0) {
-            find_done = self.parent_thread.ds_thread._model.call('message_partner_info_from_emails', [this.context.default_res_id, names_to_find]);
+            find_done = self.parent_thread.ds_thread._model.call('message_partner_info_from_emails', [[this.context.default_res_id], names_to_find]);
         }
         else {
             find_done.resolve([]);
@@ -534,7 +534,7 @@ var ThreadComposeMessage = MessageCommon.extend({
                 var new_names_to_find = _.difference(names_to_find, names_to_remove);
                 find_done = $.Deferred();
                 if (new_names_to_find.length > 0) {
-                    find_done = self.parent_thread.ds_thread._model.call('message_partner_info_from_emails', [self.context.default_res_id, new_names_to_find, true]);
+                    find_done = self.parent_thread.ds_thread._model.call('message_partner_info_from_emails', [[self.context.default_res_id], new_names_to_find, true]);
                 }
                 else {
                     find_done.resolve([]);