Problem with farsi input language in chrome

Hi,

I've used of this code as a plugin to change default input language to farsi

var keyboardLayout = {};
var langCycle = [''];
var owneditor;
var IEChangeLangFlag;

(function () {
var k = null;
var titleTimeout = null;

function showLang(langIndex) {
var langTitle = 'Language: ';
for(var i=0;i<langCycle.length;i++) {
var lang = getLangFromCycle(i) || 'default';
langTitle += (i == langIndex ? '['+lang+']' : lang) + ' ';
}

if(titleTimeout) clearTimeout(titleTimeout);
document.oldTitle = document.oldTitle || document.title;
document.title = langTitle;
titleTimeout = setTimeout(function() {
document.title = document.oldTitle;
document.oldTitle = undefined;
titleTimeout = null;
}, 1000);
}

function getLangFromCycle(i) {
return langCycle[i].lang ? langCycle[i].lang : langCycle[i];
}

function getDirectionFromCycle(i) {
return langCycle[i].direction ? langCycle[i].direction : '';
}

function getNextLangIndex(targetLang) {
var nextIndex = langCycle.length ? 0 : -1;
for(var i=0; i < langCycle.length; i++){
if(getLangFromCycle(i) == targetLang){
nextIndex = i < langCycle.length-1 ? i + 1 : 0;
}
}
return nextIndex;
}

function addEvent(elem, type, handle){
   if (elem.addEventListener)
       elem.addEventListener(type, handle, false);
   else if (elem.attachEvent)
       elem.attachEvent("on" + type, handle);
       else
       elem["on" + type] = handle;
}

function isTextField(elem){
return (elem.tagName == 'TEXTAREA') ||
(elem.tagName == 'INPUT' && elem.type && elem.type.toUpperCase() == 'TEXT');
}

function IE_OnKeyDown(e) {
if (e) k = e.which;
IEChangeLangFlag=false;
if (e.ctrlKey && e.keyCode == 0x0020)
{
IEChangeLangFlag=true;
IE_OnKeyPress(e);
}
}

function IE_OnKeyPress(e) {
var target = e.target || e.srcElement;
//if (!isTextField(target)) return;
var key = e.which || e.charCode || e.keyCode;

//read layout language from lang attribute
var lang = (owneditor.langCode || '').match(/^[a-zA-Z]{2}/) || '';
if (!lang) {
if (!langCycle.length) return true;
lang = getLangFromCycle(0);
}
// Ctrl+Space changes language (just if there's any cycle available)
if (IEChangeLangFlag && langCycle && langCycle.length > 1) {
var nextLangIndex = getNextLangIndex(lang);
if (nextLangIndex >= 0) {
showLang(nextLangIndex);
owneditor.langCode=getLangFromCycle(nextLangIndex)
}
if (e.preventDefault) e.preventDefault();
e.returnValue = false;
return false;
}
var layout = keyboardLayout[lang];
if ((!layout) ||
(e.ctrlKey || e.altKey || e.metaKey) ||
(k != 0x0020 && k < 0x0030) || //fix for opera
(key < 0x0020 || key > 0x007F))
return true;

var value =
(key == 0x0020 && e.shiftKey && layout[0x005f]) || //Shift+Space may be defined in layout[0x5f]
(layout[key - 0x0020]);

value = typeof value == 'string' ?
value :
String.fromCharCode(value);

var ds = document.selection,
ss = target.selectionStart;

if (typeof ss == 'number') { //standard browsers: http://www.w3.org/TR/html5/editing.html#dom-textarea-input-selectionstart
var sl = target.scrollLeft, st = target.scrollTop; //fix for firefox
target.value = target.value.substring(0, ss) + value + target.value.substring(target.selectionEnd, target.value.length);
var sr = ss + value.length;
target.setSelectionRange(sr, sr);
target.scrollLeft = sl;
target.scrollTop = st;
} else if (ds) { //IE: http://msdn.microsoft.com/en-us/library/ms535869(VS.85).aspx
var r = ds.createRange();
r.text = value;
r.setEndPoint('StartToEnd', r);
r.select();
} else { //unknown browsers
owneditor.insertText(value);
}

if (e.preventDefault) e.preventDefault();
e.returnValue = false;
return false;
}

var Other_OnKeyDown = function (e) {
if (e) k = e.which;
};

var Other_OnKeyPress = function (e) {
var target = e.target || e.srcElement;
//if (!isTextField(target)) return;
var key = e.which || e.charCode || e.keyCode;

//read layout language from lang attribute
var lang = (owneditor.langCode || '').match(/^[a-zA-Z]{2}/) || '';
if (!lang) {
if (!langCycle.length) return true;
lang = getLangFromCycle(0);
}

// Ctrl+Space changes language (just if there's any cycle available)
if (e.ctrlKey && key == 0x0020 && langCycle && langCycle.length > 1) {
var nextLangIndex = getNextLangIndex(lang);
if (nextLangIndex >= 0) {
showLang(nextLangIndex);
owneditor.langCode=getLangFromCycle(nextLangIndex)
}
if (e.preventDefault) e.preventDefault();
e.returnValue = false;
return false;
}
var layout = keyboardLayout[lang];
if ((!layout) ||
(e.ctrlKey || e.altKey || e.metaKey) ||
(k != 0x0020 && k < 0x0030) || //fix for opera
(key < 0x0020 || key > 0x007F))
return true;

var value =
(key == 0x0020 && e.shiftKey && layout[0x005f]) || //Shift+Space may be defined in layout[0x5f]
(layout[key - 0x0020]);

value = typeof value == 'string' ?
value :
String.fromCharCode(value);

var ds = document.selection,
ss = target.selectionStart;

if (typeof ss == 'number') { //standard browsers: http://www.w3.org/TR/html5/editing.html#dom-textarea-input-selectionstart
var sl = target.scrollLeft, st = target.scrollTop; //fix for firefox
target.value = target.value.substring(0, ss) + value + target.value.substring(target.selectionEnd, target.value.length);
var sr = ss + value.length;
target.setSelectionRange(sr, sr);
target.scrollLeft = sl;
target.scrollTop = st;
} else if (ds) { //IE: http://msdn.microsoft.com/en-us/library/ms535869(VS.85).aspx
var r = ds.createRange();
r.text = value;
r.setEndPoint('StartToEnd', r);
r.select();
} else { //unknown browsers
owneditor.insertText(value);
}

if (e.preventDefault) e.preventDefault();
e.returnValue = false;
return false;
}

CKEDITOR.plugins.add('farsi',
{
init: function (editor) {

editor.on('contentDom', function (e) {

var doc = editor.document.$;
owneditor=editor;
if (CKEDITOR.env.ie) { // If Internet Explorer.
doc.attachEvent("onkeydown", IE_OnKeyDown);
doc.attachEvent("onkeypress", IE_OnKeyPress);
} else { // If Gecko.
doc.addEventListener('keydown', Other_OnKeyDown, true);
doc.addEventListener('keypress', Other_OnKeyPress, true);
}
});

} //Init
});

})();
keyboardLayout['fa'] = [
0x0020, 0x0021, 0x061b, 0x066b, 0xfdfc, 0x066a, 0x060c, 0x06af, 0x0029, 0x0028, 0x002a, 0x002b, 0x0648, 0x002d, 0x002e, 0x002f,
0x06f0, 0x06f1, 0x06f2, 0x06f3, 0x06f4, 0x06f5, 0x06f6, 0x06f7, 0x06f8, 0x06f9, 0x003a, 0x06a9, 0x003e, 0x003d, 0x003c, 0x061f,
0x066c, 0x0624, 0x200c, 0x0698, 0x064a, 0x064d, 0x0625, 0x0623, 0x0622, 0x0651, 0x0629, 0x00bb, 0x00ab, 0x0621, 0x0654, 0x005d,
0x005b, 0x0652, 0x064b, 0x0626, 0x064f, 0x064e, 0x0670, 0x064c, 0x0653, 0x0650, 0x0643, 0x062c, 0x005c, 0x0686, 0x00d7, 0x0640,
0x200d, 0x0634, 0x0630, 0x0632, 0x06cc, 0x062b, 0x0628, 0x0644, 0x0627, 0x0647, 0x062a, 0x0646, 0x0645, 0x067e, 0x062f, 0x062e,
0x062d, 0x0636, 0x0642, 0x0633, 0x0641, 0x0639, 0x0631, 0x0635, 0x0637, 0x063a, 0x0638, 0x007d, 0x007c, 0x007b, 0x00f7, 0x200c
];
langCycle.push({lang: 'fa', direction: 'rtl'});

and its work properly until CKEditor 3.6.4 (perviouse version of CKEidtor) in chrome,firefox and IE .

but now and with new version (ckeditor 4) it has a problem just with chrome

see this image

while it should be

as a matter of fact the characters are displayed as separate and when I change the mode to source and again change it to wysiwyg it displayed correctly.

can anyone advice me?