diff --git a/extensions/TeX/enclose.js b/extensions/TeX/enclose.js
new file mode 100644
index 000000000..0bb666b2e
--- /dev/null
+++ b/extensions/TeX/enclose.js
@@ -0,0 +1,16 @@
+/*
+ *  /MathJax/extensions/TeX/enclose.js
+ *  
+ *  Copyright (c) 2010 Design Science, Inc.
+ *
+ *  Part of the MathJax library.
+ *  See http://www.mathjax.org for details.
+ * 
+ *  Licensed under the Apache License, Version 2.0;
+ *  you may not use this file except in compliance with the License.
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ */
+
+MathJax.Extension["TeX/enclose"]={version:"1.1",ALLOWED:{arrow:1,color:1,mathcolor:1,background:1,mathbackground:1,padding:1,thickness:1}};MathJax.Hub.Register.StartupHook("TeX Jax Ready",function(){var c=MathJax.InputJax.TeX,a=MathJax.ElementJax.mml,b=MathJax.Extension["TeX/enclose"].ALLOWED;c.Definitions.macros.enclose="Enclose";c.Parse.Augment({Enclose:function(g){var k=this.GetArgument(g),e=this.GetBrackets(g),j=this.ParseArg(g);var l={notation:k.replace(/,/g," ")};if(e!==""){e=e.replace(/ /g,"").split(/,/);for(var h=0,d=e.length;h<d;h++){var f=e[h].split(/[:=]/);if(b[f[0]]){if(f[1]==="true"){f[1]=true}if(f[1]==="false"){f[1]=false}l[f[0]]=f[1]}}}this.Push(a.menclose(j).With(l))}});MathJax.Hub.Startup.signal.Post("TeX enclose Ready")});MathJax.Ajax.loadComplete("[MathJax]/extensions/TeX/enclose.js");
+
diff --git a/unpacked/extensions/TeX/enclose.js b/unpacked/extensions/TeX/enclose.js
new file mode 100644
index 000000000..65a6637da
--- /dev/null
+++ b/unpacked/extensions/TeX/enclose.js
@@ -0,0 +1,85 @@
+/*************************************************************
+ *
+ *  MathJax/extensions/TeX/enclose.js
+ *  
+ *  Implements the \enclose macros, which give access from TeX to the
+ *  <menclose> tag in the MathML that underlies MathJax's internal format.
+ *  
+ *  Usage:
+ *  
+ *      \enclose{notation}{math}                  % enclose math using given notation
+ *      \enclose{notation,notation,...}{math}     % enclose with several notations
+ *      \enclose{notation}[attributes]{math}      % enclose with attributes
+ *  
+ *  ---------------------------------------------------------------------
+ *  
+ *  Copyright (c) 2011 Design Science, Inc.
+ * 
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ * 
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+MathJax.Extension["TeX/enclose"] = {
+  version: "1.1",
+  
+  //
+  //  The attributes allowed in \enclose{notation}[attributes]{math}
+  //
+  ALLOWED: {
+    arrow: 1,
+    color: 1, mathcolor: 1,
+    background: 1, mathbackground: 1,
+    padding: 1,
+    thickness: 1
+  }
+};
+  
+MathJax.Hub.Register.StartupHook("TeX Jax Ready",function () {
+  var TEX = MathJax.InputJax.TeX,
+      MML = MathJax.ElementJax.mml,
+      ALLOW = MathJax.Extension["TeX/enclose"].ALLOWED;
+  
+  //
+  //  Set up macro
+  //
+  TEX.Definitions.macros.enclose = 'Enclose';
+
+  TEX.Parse.Augment({
+    //
+    //  Implement \enclose{notation}[attr]{math}
+    //    (create <menclose notation="notation">math</menclose>)
+    //
+    Enclose: function(name) {
+      var notation = this.GetArgument(name),
+          attr = this.GetBrackets(name),
+          math = this.ParseArg(name);
+      var def = {notation: notation.replace(/,/g," ")};
+      if (attr !== "") {
+        attr = attr.replace(/ /g,"").split(/,/);
+        for (var i = 0, m = attr.length; i < m; i++) {
+          var keyvalue = attr[i].split(/[:=]/);
+          if (ALLOW[keyvalue[0]]) {
+            if (keyvalue[1] === "true") {keyvalue[1] = true}
+            if (keyvalue[1] === "false") {keyvalue[1] = false}
+            def[keyvalue[0]] = keyvalue[1];
+          }
+        }
+      }
+      this.Push(MML.menclose(math).With(def));
+    }
+  });
+
+  MathJax.Hub.Startup.signal.Post("TeX enclose Ready");
+  
+});
+
+MathJax.Ajax.loadComplete("[MathJax]/extensions/TeX/enclose.js");