i.contentWindow is null

Hello, dear CKEditor community.

I've got the next error,when submit form,that contains CKEditor component:
i.contentWindow is null
ckeditor.js (line 18)

The following configuration for CKEDitor:

       <script>
       var oScript = document.createElement("script");
       oScript.type  = "text/javascript";
       oScript.text += "var $j = jQuery.noConflict();";
            oScript.text += "$j(document).ready(function(){";
            oScript.text +=   "CKEDITOR.replace('content2', {toolbar : [";
       oScript.text += "['Source'],";
       oScript.text += "['Cut','Copy','Paste','PasteText','PasteFromWord','-','Print'],";
       oScript.text += "['Undo','Redo','-','Find','Replace','-','SelectAll','RemoveFormat'],";
       oScript.text += "['Form', 'Checkbox', 'Radio', 'TextField', 'Textarea', 'Select', 'Button', 'ImageButton', 'HiddenField'],";
       oScript.text += "'/',";
       oScript.text += "['Bold','Italic','Underline','Strike','-','Subscript','Superscript'],";
            oScript.text += "['NumberedList','BulletedList','-','Outdent','Indent','Blockquote'],";
            oScript.text += "['JustifyLeft','JustifyCenter','JustifyRight','JustifyBlock'],";
            oScript.text += "['Link','Unlink','Anchor'],";
            oScript.text += "['Image','Flash','Table','HorizontalRule','Smiley','SpecialChar','PageBreak'],";
            oScript.text += "'/',";
            oScript.text += "['Styles','Format','Font','FontSize'],";
            oScript.text += "['TextColor','BGColor'],";
            oScript.text += "['Maximize', 'ShowBlocks']],";
       oScript.text += "language : '${lang}',";
            oScript.text += "entities: false,";
            oScript.text += "filebrowserUploadUrl : '<%=request.getContextPath()%>/pages/article-ajax?command=upload',";
            oScript.text += "width:  '100%',";
            oScript.text += "height: 350,";
            oScript.text += "skin : 'v2'";
            oScript.text += "});";
            oScript.text += "new Tooltips('[title]');";
       oScript.text += "});";
       document.body.appendChild(oScript);
       </script>

CKEDitor displayed correctly on UI with all specified options above.

Textarea, which is replaced by CKEDitor in my .jsp looks like:

<textarea name="content2" rows="" cols="">${articleForm.content}</textarea>

Perhaps, reason is that several instances of CKEDitor created, i read on other branches of forum.
I tried destroy() function, it didn't help.

Don't know what to do more...
May be you faced such a problem?

Thank you for help.

--
Sergei