diff --git a/lib/ace/worker/worker_client.js b/lib/ace/worker/worker_client.js
index a53f1acf..743bd0ed 100644
--- a/lib/ace/worker/worker_client.js
+++ b/lib/ace/worker/worker_client.js
@@ -35,7 +35,7 @@ var oop = require("../lib/oop");
 var EventEmitter = require("../lib/event_emitter").EventEmitter;
 var config = require("../config");
 
-var WorkerClient = function(topLevelNamespaces, mod, classname) {
+var WorkerClient = function(topLevelNamespaces, mod, classname, workerUrl) {
     this.$sendDeltaQueue = this.$sendDeltaQueue.bind(this);
     this.changeListener = this.changeListener.bind(this);
     this.onMessage = this.onMessage.bind(this);
@@ -43,13 +43,12 @@ var WorkerClient = function(topLevelNamespaces, mod, classname) {
     // nameToUrl is renamed to toUrl in requirejs 2
     if (require.nameToUrl && !require.toUrl)
         require.toUrl = require.nameToUrl;
-
-    var workerUrl;
+    
     if (config.get("packaged") || !require.toUrl) {
-        workerUrl = config.moduleUrl(mod, "worker");
+        workerUrl = workerUrl || config.moduleUrl(mod, "worker");
     } else {
         var normalizePath = this.$normalizePath;
-        workerUrl = normalizePath(require.toUrl("ace/worker/worker.js", null, "_"));
+        workerUrl = workerUrl || normalizePath(require.toUrl("ace/worker/worker.js", null, "_"));
 
         var tlns = {};
         topLevelNamespaces.forEach(function(ns) {
@@ -59,12 +58,12 @@ var WorkerClient = function(topLevelNamespaces, mod, classname) {
 
     try {
         this.$worker = new Worker(workerUrl);
-    } catch ( e ) {
-        if ( e instanceof DOMException ) {
+    } catch(e) {
+        if (e instanceof window.DOMException) {
             // Likely same origin problem. Use importScripts from a shim Worker
-            var blob = this.blobWorker(workerUrl),
-                URL = URL || webkitURL,
-                blobURL = URL.createObjectURL(blob);
+            var blob = this.$workerBlob(workerUrl);
+            var URL = window.URL || window.webkitURL;
+            var blobURL = URL.createObjectURL(blob);
 
             this.$worker = new Worker(blobURL);
             URL.revokeObjectURL(blobURL);
@@ -74,9 +73,9 @@ var WorkerClient = function(topLevelNamespaces, mod, classname) {
     }
     this.$worker.postMessage({
         init : true,
-        tlns: tlns,
-        module: mod,
-        classname: classname
+        tlns : tlns,
+        module : mod,
+        classname : classname
     });
 
     this.callbackId = 1;
@@ -179,17 +178,13 @@ var WorkerClient = function(topLevelNamespaces, mod, classname) {
             this.emit("change", {data: q});
     };
 
-    this.blobWorker = function(workerUrl) {
-        var script = 'importScripts("' + workerUrl + '");',
-            blob;
+    this.$workerBlob = function(workerUrl) {
+        var script = 'importScripts("' + workerUrl + '");';
         try {
-            blob = new Blob(
-                [script],
-                { 'type' : 'application/javascript' }
-            );
+            var blob = new Blob([script], {'type': 'application/javascript'});
         } catch (e) { // Backwards-compatibility
-            var BlobBuilder = window.BlobBuilder || window.WebKitBlobBuilder || window.MozBlobBuilder,
-                blobBuilder = new BlobBuilder();
+            var BlobBuilder = window.BlobBuilder || window.WebKitBlobBuilder || window.MozBlobBuilder;
+            var blobBuilder = new BlobBuilder();
             blobBuilder.append(script);
             blob = blobBuilder.getBlob('application/javascript');
         }