diff --git a/js/h5p-event-dispatcher.js b/js/h5p-event-dispatcher.js
index 25a3b5c..204fda9 100644
--- a/js/h5p-event-dispatcher.js
+++ b/js/h5p-event-dispatcher.js
@@ -40,7 +40,7 @@ H5P.EventDispatcher = (function () {
       if (thisArg === undefined) {
         thisArg = self;
       }
-      if (!(listener instanceof Function)) {
+      if (typeof listener !== 'function') {
         throw TypeError('listener must be a function');
       }
 
diff --git a/js/h5p-x-api.js b/js/h5p-x-api.js
index 0cf9a84..77b9357 100644
--- a/js/h5p-x-api.js
+++ b/js/h5p-x-api.js
@@ -3,6 +3,10 @@ var H5P = H5P || {};
 // Create object where external code may register and listen for H5P Events
 H5P.externalDispatcher = new H5P.EventDispatcher();
 
+if (window.top !== window.self && window.top.H5P !== undefined && window.top.H5P.externalDispatcher !== undefined) {
+  H5P.externalDispatcher.on('xAPI', window.top.H5P.externalDispatcher.trigger);
+}
+
 // EventDispatcher extensions
 
 /**