diff --git a/lib/ace/edit_session.js b/lib/ace/edit_session.js
index 52dc7789..bf0c0a51 100644
--- a/lib/ace/edit_session.js
+++ b/lib/ace/edit_session.js
@@ -898,29 +898,6 @@ var EditSession = function(text, mode) {
     };
 
     this.$modes = {};
-    this._loadMode = function(name, callback) {
-        if (!this.$modes["null"])
-            this.$modes["null"] = this.$modes["ace/mode/text"] = new TextMode();
-
-        if (this.$modes[name])
-            return callback(this.$modes[name]);
-
-        var _self = this;
-        config.loadModule(["mode", name], function(module) {
-            if (_self.$modes[name])
-                return callback(_self.$modes[name]);
-            if (module && module.Mode) {
-                _self.$modes[name] = new module.Mode();
-                _self.$modes[name].$id = name;
-                callback(_self.$modes[name]);
-            }
-        });
-
-        // set mode to text until loading is finished
-        if (!this.$mode)
-            this.$onChangeMode(_self.$modes["ace/mode/text"], true);
-    };
-
 
     /**
     * Sets a new text mode for the `EditSession`. This method also emits the `'changeMode'` event. If a [[BackgroundTokenizer `BackgroundTokenizer`]] is set, the `'tokenizerUpdate'` event is also emitted.
@@ -930,21 +907,44 @@ var EditSession = function(text, mode) {
     this.$mode = null;
     this.$modeId = null;
     this.setMode = function(mode) {
-        // load on demand
-        if (!mode || typeof mode === "string") {
-            var modeName = mode || "ace/mode/text";
-            if (this.$modeId === modeName)
-                return;
+        if (mode && typeof mode === "object") {
+            if (mode.getTokenizer)
+                return this.$onChangeMode(mode);
+            var options = mode;
+            var path = options.path;
+        } else {
+            path = mode || "ace/mode/text";
+        }
 
-            this.$modeId = modeName;
-            this._loadMode(modeName, function(mode) {
-                if (this.$modeId === modeName)
-                    this.$onChangeMode(mode);
-            }.bind(this));
-        } else
-            this.$onChangeMode(mode);
+        // this is needed if ace isn't on require path (e.g tests in node)
+        if (!this.$modes["ace/mode/text"])
+            this.$modes["ace/mode/text"] = new TextMode();
+
+        if (this.$modes[path] && !options)
+            return this.$onChangeMode(this.$modes[path]);
+
+        // load on demand
+        this.$modeId = path;
+        config.loadModule(["mode", path], function(m) {
+            if (this.$modeId !== path)
+                return;
+            if (this.$modes[path] && !options)
+                return this.$onChangeMode(this.$modes[path]);
+            if (m && m.Mode) {
+                m = new m.Mode(options);
+                if (!options) {
+                    this.$modes[path] = m;
+                    m.$id = path;
+                }
+                this.$onChangeMode(m)
+            }
+        }.bind(this));
+
+        // set mode to text until loading is finished
+        if (!this.$mode)
+            this.$onChangeMode(this.$modes["ace/mode/text"], true);
     };
-    
+
     this.$onChangeMode = function(mode, $isPlaceholder) {
         if (this.$mode === mode) return;
         this.$mode = mode;