diff --git a/lib/transports/polling-xhr.js b/lib/transports/polling-xhr.js
index 25b79a5a..c80beec2 100644
--- a/lib/transports/polling-xhr.js
+++ b/lib/transports/polling-xhr.js
@@ -228,8 +228,8 @@ Request.prototype.onData = function (data) {
  * @api private
  */
 
-Request.prototype.onError = function () {
-  this.emit('error');
+Request.prototype.onError = function (err) {
+  this.emit('error', err);
   this.cleanup();
 }