Internet Explorer + AJAX + UTF encoding problem

[pacinpm]

Hi, I have problem with AJAX responce in Internet Explorer. I have a form with button and backing bean.

<h:outputText id="test" value="#{geocodeBean.testUTF()}"/>
<h:commandButton value="test" type="button">
 <f:ajax event="action" execute="@form" render="test"/>
</h:commandButton>

public String testUTF(){
        return "ÓĄŚŁŻŹĆŃĘóęąśżźćń test utf";
    }

I am using Glassfish as a appserver. Everything works OK in Opera, Firefox and Chrome but in Internet Explorer I get error when I run AJAX responce.

Error states (translation from Polish): malformedXML: XML Parsing Error, invalid character in text

It always points to first non Latin character.

I tried different DOCTYPEs of pages but AJAX is always returned as XML with UTF-8 as encoding.

What can I do to make it work in IE?

PS. Below is infromation from Firefox Firebug:

Request headers

Host: localhost:8080
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; pl; rv:1.9.2.12) Gecko/20101026 Firefox/3.6.12
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: pl,en-us;q=0.7,en;q=0.3
Accept-Encoding: gzip,deflate
Accept-Charset: ISO-8859-2,utf-8;q=0.7,*;q=0.7
Keep-Alive: 115
Connection: keep-alive
Faces-Request: partial/ajax
Content-Type: application/x-www-form-urlencoded; charset=UTF-8
Referer: http://localhost:8080/index.xhtml
Content-Length: 437
Cookie: JSESSIONID=bf0534da72c200d936f3ace73f51; treeForm:tree-hi=
Pragma: no-cache
Cache-Control: no-cache

Answer headers

X-Powered-By	Servlet/3.0, JSF/2.0
Server	GlassFish Server Open Source Edition 3.0.1
Cache-Control	no-cache
Content-Type	text/xml;charset=UTF-8
Content-Length	313
Date	Tue, 30 Nov 2010 09:05:44 GMT

Answer

<?xml version="1.0" encoding="utf-8"?>
<partial-response><changes><update id="main:geo:test"><![CDATA[<span id="main:geo:test">ÓĄŚŁŻŹĆŃĘóęąśżźćń test utf</span>]]></update><update id="javax.faces.ViewState"><![CDATA[1401236602716723051:-877922355409299404]]></update></changes></partial-response>