diff --git a/demo/kitchen-sink/demo.js b/demo/kitchen-sink/demo.js
index 08c5098c..b12eb95b 100644
--- a/demo/kitchen-sink/demo.js
+++ b/demo/kitchen-sink/demo.js
@@ -62,6 +62,8 @@ var fillDropdown = util.fillDropdown;
 var bindCheckbox = util.bindCheckbox;
 var bindDropdown = util.bindDropdown;
 
+var ElasticTabstopsLite = require("ace/ext/elastic_tabstops_lite").ElasticTabstopsLite;
+
 /*********** create editor ***************************/
 var container = document.getElementById("editor-container");
 
@@ -362,7 +364,7 @@ bindCheckbox("read_only", function(checked) {
 
 bindDropdown("split", function(value) {
     var sp = env.split;
-    if (value == "none") {        
+    if (value == "none") {
         sp.setSplits(1);
     } else {
         var newEditor = (sp.getSplits() == 1);
@@ -377,6 +379,12 @@ bindDropdown("split", function(value) {
     }
 });
 
+
+bindCheckbox("elastic_tabstops", function(checked) {
+    env.editor.setOption("useElasticTabstops", checked);
+});
+
+
 function synchroniseScrolling() {
     var s1 = env.split.$editors[0].session;
     var s2 = env.split.$editors[1].session;
diff --git a/kitchen-sink.html b/kitchen-sink.html
index c846e2aa..33bc19a7 100644
--- a/kitchen-sink.html
+++ b/kitchen-sink.html
@@ -241,6 +241,14 @@
         <input type="checkbox" id="fade_fold_widgets">
       </td>
     </tr>
+    <tr>
+      <td >
+        <label for="elastic_tabstops">Enable Elastic Tabstops</label>
+      </td>
+      <td>
+        <input type="checkbox" id="elastic_tabstops">
+      </td>
+    </tr>
     <tr>
       <td >
         <label for="highlight_token">Show token info</label>
diff --git a/lib/ace/document.js b/lib/ace/document.js
index b0d3811c..fb3734a2 100644
--- a/lib/ace/document.js
+++ b/lib/ace/document.js
@@ -227,7 +227,7 @@ var Document = function(text) {
     * [Given a range within the document, this function returns all the text within that range as a single string.]{: #Document.getTextRange.desc}
     * @param {Range} range The range to work with
     * 
-    * 
+    * @returns {String}
     **/
     this.getTextRange = function(range) {
         if (range.start.row == range.end.row) {
@@ -252,8 +252,8 @@ var Document = function(text) {
     };
 
     /**
-    * Inserts a block of `text` and the indicated `position`.
-    * @param {Object} position The position to start inserting at 
+    * Inserts a block of `text` at the indicated `position`.
+    * @param {Object} position The position to start inserting at; it's an object that looks like `{ row: row, column: column}`
     * @param {String} text A chunk of text to insert
     * @returns {Object} The position ({row, column}) of the last line of `text`. If the length of `text` is 0, this function simply returns `position`. 
     *
@@ -379,7 +379,7 @@ var Document = function(text) {
 
     /**
     * Inserts `text` into the `position` at the current row. This method also triggers the `'change'` event.
-    * @param {Object} position The position to insert at
+    * @param {Object} position The position to insert at; it's an object that looks like `{ row: row, column: column}`
     * @param {String} text A chunk of text
     * @returns {Object} Returns an object containing the final row and column, like this:  
     *     ```
diff --git a/lib/ace/edit_session.js b/lib/ace/edit_session.js
index 72a70034..2258d0fc 100644
--- a/lib/ace/edit_session.js
+++ b/lib/ace/edit_session.js
@@ -1119,25 +1119,25 @@ var EditSession = function(text, mode) {
     };
 
     /** 
-    * Inserts a block of `text` and the indicated `position`.
+     * Inserts a block of `text` and the indicated `position`.
      * @param {Object} position The position {row, column} to start inserting at
      * @param {String} text A chunk of text to insert
      * @returns {Object} The position of the last line of `text`. If the length of `text` is 0, this function simply returns `position`.
-    *
-    *
-    **/
+     *
+     *
+     **/
     this.insert = function(position, text) {
         return this.doc.insert(position, text);
     };
 
     /** 
-    * Removes the `range` from the document.
+     * Removes the `range` from the document.
      * @param {Range} range A specified Range to remove
      * @returns {Object} The new `start` property of the range, which contains `startRow` and `startColumn`. If `range` is empty, this function returns the unmodified value of `range.start`.
-    *
+     *
      * @related Document.remove
-    *
-    **/
+     *
+     **/
     this.remove = function(range) {
         return this.doc.remove(range);
     };
diff --git a/lib/ace/ext/elastic_tabstops_lite.js b/lib/ace/ext/elastic_tabstops_lite.js
new file mode 100644
index 00000000..b9e9891f
--- /dev/null
+++ b/lib/ace/ext/elastic_tabstops_lite.js
@@ -0,0 +1,319 @@
+/* ***** BEGIN LICENSE BLOCK *****
+ * Distributed under the BSD license:
+ *
+ * Copyright (c) 2012, Ajax.org B.V.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *     * Neither the name of Ajax.org B.V. nor the
+ *       names of its contributors may be used to endorse or promote products
+ *       derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL AJAX.ORG B.V. BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+define(function(require, exports, module) {
+"use strict";
+
+var ElasticTabstopsLite = function(editor) {
+    this.$editor = editor;
+    var self = this;
+    var changedRows = [];
+    var recordChanges = false;
+    this.onAfterExec = function() {
+        recordChanges = false;
+        self.processRows(changedRows);
+        changedRows = [];
+    };
+    this.onExec = function() {
+        recordChanges = true;
+    };
+    this.onChange = function(e) {
+        var range = e.data.range
+        if (recordChanges) {
+            if (changedRows.indexOf(range.start.row) == -1)
+                changedRows.push(range.start.row);
+            if (range.end.row != range.start.row)
+                changedRows.push(range.end.row);
+        }
+    };
+};
+
+(function() {
+    this.processRows = function(rows) {
+        this.$inChange = true;
+        var checkedRows = [];
+
+        for (var r = 0, rowCount = rows.length; r < rowCount; r++) {
+            var row = rows[r];
+
+            if (checkedRows.indexOf(row) > -1)
+                continue;
+
+            var cellWidthObj = this.$findCellWidthsForBlock(row);
+            var cellWidths = this.$setBlockCellWidthsToMax(cellWidthObj.cellWidths);
+            var rowIndex = cellWidthObj.firstRow;
+
+            for (var w = 0, l = cellWidths.length; w < l; w++) {
+                var widths = cellWidths[w];
+                checkedRows.push(rowIndex);
+                this.$adjustRow(rowIndex, widths);
+                rowIndex++;
+            }
+        }
+        this.$inChange = false;
+    };
+
+    this.$findCellWidthsForBlock = function(row) {
+        var cellWidths = [], widths;
+
+        // starting row and backward
+        var rowIter = row;
+        while (rowIter >= 0) {
+            widths = this.$cellWidthsForRow(rowIter);
+            if (widths.length == 0)
+                break;
+
+            cellWidths.unshift(widths);
+            rowIter--;
+        }
+        var firstRow = rowIter + 1;
+
+        // forward (not including starting row)
+        rowIter = row;
+        var numRows = this.$editor.session.getLength();
+
+        while (rowIter < numRows - 1) {
+            rowIter++;
+
+            widths = this.$cellWidthsForRow(rowIter);
+            if (widths.length == 0)
+                break;
+
+            cellWidths.push(widths);
+        }
+
+        return { cellWidths: cellWidths, firstRow: firstRow };
+    };
+
+    this.$cellWidthsForRow = function(row) {
+        var selectionColumns = this.$selectionColumnsForRow(row);
+        // todo: support multicursor
+
+        var tabs = [-1].concat(this.$tabsForRow(row));
+        var widths = tabs.map(function (el) { return 0; } ).slice(1);
+        var line = this.$editor.session.getLine(row);
+
+        for (var i = 0, len = tabs.length - 1; i < len; i++) {
+            var leftEdge = tabs[i]+1;
+            var rightEdge = tabs[i+1];
+
+            var rightmostSelection = this.$rightmostSelectionInCell(selectionColumns, rightEdge);
+            var cell = line.substring(leftEdge, rightEdge);
+            widths[i] = Math.max(cell.replace(/\s+$/g,'').length, rightmostSelection - leftEdge);
+        }
+        
+        return widths;
+    };
+
+    this.$selectionColumnsForRow = function(row) {
+        var selections = [], cursor = this.$editor.getCursorPosition();
+        if (this.$editor.session.getSelection().isEmpty()) {
+            // todo: support multicursor
+            if (row == cursor.row)
+                selections.push(cursor.column);   
+        }
+
+        return selections;
+    };
+
+    this.$setBlockCellWidthsToMax = function(cellWidths) {
+        var startingNewBlock = true, blockStartRow, blockEndRow, maxWidth;
+        var columnInfo = this.$izip_longest(cellWidths);
+
+        for (var c = 0, l = columnInfo.length; c < l; c++) {
+            var column = columnInfo[c];
+            if (!column.push) {
+                console.error(column);
+                continue;
+            }
+            // add an extra None to the end so that the end of the column automatically
+            // finishes a block
+            column.push(NaN);
+
+            for (var r = 0, s = column.length; r < s; r++) {
+                var width = column[r];
+                if (startingNewBlock) {
+                    blockStartRow = r;
+                    maxWidth = 0;
+                    startingNewBlock = false;
+                }
+                if (isNaN(width)) {
+                    // block ended
+                    blockEndRow = r;
+
+                    for (var j = blockStartRow; j < blockEndRow; j++) {
+                        cellWidths[j][c] = maxWidth;
+                    }
+                    startingNewBlock = true;
+                }
+
+                maxWidth = Math.max(maxWidth, width);
+            }
+        }
+
+        return cellWidths;
+    };
+
+    this.$rightmostSelectionInCell = function(selectionColumns, cellRightEdge) {
+        var rightmost = 0;
+
+        if (selectionColumns.length) {
+            var lengths = [];
+            for (var s = 0, length = selectionColumns.length; s < length; s++) {
+                if (selectionColumns[s] <= cellRightEdge)
+                    lengths.push(s);
+                else 
+                    lengths.push(0);
+            }
+            rightmost = Math.max.apply(Math, lengths);
+        }
+
+        return rightmost;
+    };
+
+    this.$tabsForRow = function(row) {
+        var rowTabs = [], line = this.$editor.session.getLine(row),
+            re = /\t/g, match;
+
+        while ((match = re.exec(line)) != null) {
+            rowTabs.push(match.index);
+        }
+
+        return rowTabs;
+    };
+
+    this.$adjustRow = function(row, widths) {
+        var rowTabs = this.$tabsForRow(row);
+
+        if (rowTabs.length == 0)
+            return;
+        
+        var bias = 0, location = -1;
+        
+        // this always only contains two elements, so we're safe in the loop below
+        var expandedSet = this.$izip(widths, rowTabs);
+
+        for (var i = 0, l = expandedSet.length; i < l; i++) {
+            var w = expandedSet[i][0], it = expandedSet[i][1];
+            location += 1 + w;
+            it += bias;
+            var difference = location - it;
+
+            if (difference == 0)
+                continue;
+
+            var partialLine = this.$editor.session.getLine(row).substr(0, it );
+            var strippedPartialLine = partialLine.replace(/\s*$/g, "");
+            var ispaces = partialLine.length - strippedPartialLine.length;
+
+            if (difference > 0) {
+                // put the spaces after the tab and then delete the tab, so any insertion
+                // points behave as expected
+                this.$editor.session.getDocument().insertInLine({row: row, column: it + 1}, Array(difference + 1).join(" ") + "\t");
+                this.$editor.session.getDocument().removeInLine(row, it, it + 1);
+
+                bias += difference;
+            }
+
+            if (difference < 0 && ispaces >= -difference) {
+                this.$editor.session.getDocument().removeInLine(row, it + difference, it);
+                bias += difference;
+            }
+        }
+    };
+
+    // the is a (naive) Python port--but works for these purposes
+    this.$izip_longest = function(iterables) {
+        if (!iterables[0])
+            return [];
+        var longest = iterables[0].length;
+        var iterablesLength = iterables.length;
+
+        for (var i = 1; i < iterablesLength; i++) {
+            var iLength = iterables[i].length;
+            if (iLength > longest)
+                longest = iLength;
+        }
+        
+        var expandedSet = [];
+
+        for (var l = 0; l < longest; l++) {
+            var set = [];
+            for (var i = 0; i < iterablesLength; i++) {
+                if (iterables[i][l] === "")
+                    set.push(NaN);
+                else
+                    set.push(iterables[i][l]);
+            }
+
+            expandedSet.push(set);
+        }
+        
+
+        return expandedSet;
+    };
+
+    // an even more (naive) Python port
+    this.$izip = function(widths, tabs) {
+        // grab the shorter size
+        var size = widths.length >= tabs.length ? tabs.length : widths.length;
+        
+        var expandedSet = [];
+        for (var i = 0; i < size; i++) {
+            var set = [ widths[i], tabs[i] ];
+            expandedSet.push(set);
+        }
+        return expandedSet;
+    };
+
+}).call(ElasticTabstopsLite.prototype);
+
+exports.ElasticTabstopsLite = ElasticTabstopsLite;
+
+var Editor = require("../editor").Editor;
+require("../config").defineOptions(Editor.prototype, "editor", {
+    useElasticTabstops: {
+        set: function(val) {
+            if (val) {
+                if (!this.elasticTabstops)
+                    this.elasticTabstops = new ElasticTabstopsLite(this);
+                this.commands.on("afterExec", this.elasticTabstops.onAfterExec);
+                this.commands.on("exec", this.elasticTabstops.onExec);
+                this.on("change", this.elasticTabstops.onChange);
+            } else if (this.elasticTabstops) {
+                this.commands.removeListener("afterExec", this.elasticTabstops.onAfterExec);
+                this.commands.removeListener("exec", this.elasticTabstops.onExec);
+                this.removeListener("change", this.elasticTabstops.onChange);
+            }
+        }
+    }
+});
+
+});
\ No newline at end of file
diff --git a/lib/ace/ext/searchbox.js b/lib/ace/ext/searchbox.js
index eecac88c..8efd08a7 100644
--- a/lib/ace/ext/searchbox.js
+++ b/lib/ace/ext/searchbox.js
@@ -43,12 +43,12 @@ dom.importCssString(searchboxCss, "ace_searchbox");
 var html = '<div class="ace_search right">\
     <button action="hide" class="ace_searchbtn_close"></button>\
     <div class="ace_search_form">\
-        <input class="ace_search_field" placeholder="Search for" spellcheck="false">\
+        <input class="ace_search_field" placeholder="Search for" spellcheck="false"></input>\
         <button action="findNext" class="ace_searchbtn next"></button>\
         <button action="findPrev" class="ace_searchbtn prev"></button>\
     </div>\
     <div class="ace_replace_form">\
-        <input class="ace_search_field" placeholder="Replace with" spellcheck="false">\
+        <input class="ace_search_field" placeholder="Replace with" spellcheck="false"></input>\
         <button action="replace" class="ace_replacebtn">Replace</button>\
         <button action="replaceAll" class="ace_replacebtn">All</button>\
     </div>\