diff --git a/wagtail/wagtailimages/static/wagtailimages/js/add-multiple.js b/wagtail/wagtailimages/static/wagtailimages/js/add-multiple.js
index dd9525007..d08d45863 100644
--- a/wagtail/wagtailimages/static/wagtailimages/js/add-multiple.js
+++ b/wagtail/wagtailimages/static/wagtailimages/js/add-multiple.js
@@ -1,7 +1,7 @@
 $(function(){
     // Redirect users that don't support filereader
     if(!$('html').hasClass('filereader')){
-        document.location.href = window.simple_upload_url;
+        document.location.href = window.fileupload_opts.simple_upload_url;
         return false;
     }
 
@@ -14,15 +14,15 @@ $(function(){
         dataType: 'html',
         sequentialUploads: true,
         dropZone: $('.drop-zone'),
-        acceptFileTypes: window.accepted_file_types,
-        maxFileSize: window.max_file_size,
+        acceptFileTypes: window.fileupload_opts.accepted_file_types,
+        maxFileSize: window.fileupload_opts.max_file_size,
         previewMinWidth:150,
         previewMaxWidth:150,
         previewMinHeight:150,
         previewMaxHeight:150,
         messages: {
-            acceptFileTypes: window.message_accepted_file_types,
-            maxFileSize: window.messages_max_filesize
+            acceptFileTypes: window.fileupload_opts.messages.accepted_file_types,
+            maxFileSize: window.fileupload_opts.messages.max_file_size
         },
         add: function (e, data) {
             var $this = $(this);
diff --git a/wagtail/wagtailimages/templates/wagtailimages/multiple/add.html b/wagtail/wagtailimages/templates/wagtailimages/multiple/add.html
index 354325366..f8dda2d30 100644
--- a/wagtail/wagtailimages/templates/wagtailimages/multiple/add.html
+++ b/wagtail/wagtailimages/templates/wagtailimages/multiple/add.html
@@ -70,11 +70,15 @@
 
     {% url 'wagtailadmin_tag_autocomplete' as autocomplete_url %}
     <script>
-        window.accepted_file_types = /(\.|\/)(gif|jpe?g|png)$/i; //must be regex
-        window.message_max_filesize = "max filesize message";
-        window.message_accepted_file_types = "filetypes message";
-        window.max_file_size = {{ max_filesize }}; //numeric format
-        window.simple_upload_url = "{% url 'wagtailimages_add_image' %}";
+        window.fileupload_opts = {
+            simple_upload_url: "{% url 'wagtailimages_add_image' %}",
+            accepted_file_types: /(\.|\/)(gif|jpe?g|png)$/i, //must be regex
+            max_file_size: {{ max_filesize }}, //numeric format
+            messages: {
+                max_file_size: "max filesize message",
+                accepted_file_types: "filetypes message"
+            }
+        }
         window.tagit_opts = {
             autocomplete: {source: "{{ autocomplete_url|addslashes }}"}
         };