diff --git a/src/converse-ping.js b/src/converse-ping.js
index 9482f46e5..74038a182 100644
--- a/src/converse-ping.js
+++ b/src/converse-ping.js
@@ -56,7 +56,9 @@
             };
 
             _converse.registerPongHandler = function () {
-                _converse.connection.disco.addFeature(Strophe.NS.PING);
+                if (!_.isUndefined(_converse.connection.disco)) {
+                    _converse.connection.disco.addFeature(Strophe.NS.PING);
+                }
                 _converse.connection.ping.addPingHandler(_converse.pong);
             };
 
diff --git a/src/utils.js b/src/utils.js
index 222d8db62..72d57eaaf 100755
--- a/src/utils.js
+++ b/src/utils.js
@@ -6,7 +6,7 @@
 // Copyright (c) 2012-2017, Jan-Carel Brand <jc@opkode.com>
 // Licensed under the Mozilla Public License (MPLv2)
 //
-/*global define, escape, locales, Jed */
+/*global define, escape, locales, window */
 (function (root, factory) {
     define([
         "sizzle",
@@ -86,8 +86,11 @@
     // Translation machinery
     // ---------------------
     u.__ = function (str) {
+        if (_.isUndefined(window.Jed)) {
+            return str;
+        }
         if (!u.isConverseLocale(this.locale) || this.locale === 'en') {
-            return Jed.sprintf.apply(Jed, arguments);
+            return Jed.sprintf.apply(window.Jed, arguments);
         }
         if (typeof this.jed === "undefined") {
             this.jed = new Jed(window.JSON.parse(locales[this.locale]));