diff --git a/lib/ace/keyboard/emacs.js b/lib/ace/keyboard/emacs.js
index b0ef90ca..4d3dfb7b 100644
--- a/lib/ace/keyboard/emacs.js
+++ b/lib/ace/keyboard/emacs.js
@@ -51,17 +51,6 @@ exports.handler = new HashHandler();
 
 var initialized = false;
 
-// When mark is set, keyboard cursor movement commands become selection
-// modification commands. This is a little different than emacs. In
-// emacs, keyboard cursor movement always sets mark, but it does not
-// highlight the region unless mark has been otherwise explicitly set
-// and transient-mark-mode is on.
-// In ACE, there is no concept of a region that is not highlighted,
-// so we just work with highlighted area === region. It would probably be
-// confusing to most users anyway if a cut command, say, were to delete an
-// area that was not highlighted.
-var markMode;
-
 exports.handler.attach = function(editor) {
     if (!initialized) {
         initialized = true;
@@ -95,7 +84,13 @@ exports.handler.attach = function(editor) {
     // in emacs, gotowordleft/right should not count a space as a word..
     editor.session.$selectLongWords = true;
     
-    markMode = false;
+    exports.markMode = function() {
+        return editor.session.$emacsMark;
+    }
+
+    exports.setMarkMode = function(p) {
+        editor.session.$emacsMark = p;
+    }
 
     editor.on("click",$resetMarkMode);
 
@@ -103,6 +98,9 @@ exports.handler.attach = function(editor) {
     // kitchen sink seems to reload the session after loading the kb handler.
     editor.on("changeSession",function(e) {
         e.session.$selectLongWords = true;
+        if (! e.session.hasOwnProperty('$emacsMark')) {
+            e.session.$emacsMark = false;
+        }
     });
 
     editor.renderer.screenToTextCoordinates = screenToTextBlockCoordinates;
@@ -121,7 +119,7 @@ exports.handler.detach = function(editor) {
 };
 
 var $resetMarkMode = function(e) {
-    markMode = null;
+    e.editor.session.$emacsMark = null;
 }
 
 var keys = require("../lib/keys").KEY_MODS;
@@ -153,7 +151,7 @@ exports.handler.bindKey = function(key, command) {
 
 exports.handler.handleKeyboard = function(data, hashId, key, keyCode) {
     if (hashId == -1) {
-        markMode = null;
+        exports.setMarkMode(null);
         if (data.count) {
             var str = Array(data.count + 1).join(key);
             data.count = null;
@@ -199,7 +197,7 @@ exports.handler.handleKeyboard = function(data, hashId, key, keyCode) {
         command = command.command;
         if (command == "goorselect") {
             command = args[0];
-            if (markMode) {
+            if (exports.markMode()) {
                 command = args[1];
             }
             args = null;
@@ -210,7 +208,7 @@ exports.handler.handleKeyboard = function(data, hashId, key, keyCode) {
         if (command == "insertstring" ||
            command == "splitline" ||
            command == "togglecomment") {
-            markMode = null;
+            exports.setMarkMode(null);
         }
         command = this.commands[command] || data.editor.commands.commands[command];
     }
@@ -336,25 +334,29 @@ exports.handler.addCommands({
         editor.multiSelect.toggleBlockSelection();
     },
     setMark:  function(editor) {
+        // Emulate emacs highlighting behaviour in transient-mark-mode.
         // Sets mark-mode and clears current selection.
-        // When in mark-mode, "goto" commands become "select" commands.
+        // When mark is set, keyboard cursor movement commands become 
+        // selection modification commands. That is,
+        // "goto" commands become "select" commands.
         // Any insertion or mouse click resets mark-mode.
+        // setMark twice in a row at the same place resets markmode
+        var markMode = exports.markMode();
 
         if (markMode) {
 
             cp = editor.getCursorPosition();
             if (editor.selection.isEmpty() &&
                markMode.row == cp.row && markMode.column == cp.column) {
-                // setMark twice in a row at the same place
-                // resets markmode
-                markMode = null;
-                console.log("Mark mode off");
+                exports.setMarkMode(null);
+                // console.log("Mark mode off");
                 return;
             }
         }
 
         // turn on mark mode
         markMode = editor.getCursorPosition();
+        exports.setMarkMode(markMode);
         editor.selection.setSelectionAnchor(markMode.row, markMode.column);
         
     },
@@ -385,7 +387,7 @@ exports.handler.addCommands({
         multiselectAction: "forEach"
     },
     killLine: function(editor) {
-        markMode = null;
+        exports.setMarkMode(null);
         var pos = editor.getCursorPosition();
 
         if (pos.column == 0 &&