diff --git a/web_socket.js b/web_socket.js
index 06cc5d0..6845d30 100644
--- a/web_socket.js
+++ b/web_socket.js
@@ -25,6 +25,13 @@
     logger = {log: function(){ }, error: function(){ }};
   }
   
+  var isIE9;
+  if(navigator.userAgent.indexOf("Trident/5")>-1) {
+  	isIE9 = true;
+  } else {
+  	isIE9 = false;
+  }
+  
   // swfobject.hasFlashPlayerVersion("10.0.0") doesn't work with Gnash.
   if (swfobject.getFlashPlayerVersion().major < 10) {
     logger.error("Flash Player >= 10.0.0 is required.");
@@ -203,7 +210,7 @@
   };
   
   WebSocket.prototype.__createMessageEvent = function(type, data) {
-    if (document.createEvent && window.MessageEvent && !window.opera) {
+    if (document.createEvent && window.MessageEvent && !window.opera && !isIE9) {
       var event = document.createEvent("MessageEvent");
       event.initMessageEvent("message", false, false, data, null, null, window, null);
       return event;