Parsing XML from php using jquery

I have a script in php that writes XML.

I use an ajax call to read that XML.

$.ajax({
        url: "http://blablabla.com/myscript.php",
        data: requestVars,
        dataType: 'xml',
        success: function(xml){
            XMLParser(xml);
            },
        error: function(xhr,err){
            alert("readyState: "+ xhr.readyState + "\nstatus: " + xhr.status + "\nerror:" + err);
            alert("responseText: " + xhr.responseText);
            }
    });

On php I have this:

<?php
header('Content-Type: application/xml; charset=UTF-8');

...
?>

(tried both with application/xml and text/xml)

Problem:

Works like a charm in Google Chrome, fails on IE9 and Firefox wit开发者_JAVA百科h readyState: 4, status: 200 and Error: parsererror

EDIT: A little piece of sample XML:

<?xml version='1.0' encoding='utf-8'?>

    <Index Title="asdsad" isImg="0">
      <Categories>
        <Cat Id="13">
          <Title>Movies</Title>
        </Cat>
        <Cat Id="15">
          <Title>Books</Title>
        </Cat>
      </Categories>
      <Subject Id="141" Open="0">
        <Title>Subject A</Title>
        <Resource Id="553" Level="2">
          <Title>Resource A1</Title>
        </Resource>
        </Subject>
    </Index>

Are you sure that your editor setup encode is utf-8 and you save this xml/php file as utf-8?

Use firebug into firefox to check what error is generating your call. Maybe is just some not valid utf-8 character inside your xml.

It might be that jQuery is unable to parse the XML, but your XMLParser might be.

If that is the case, you can process any result you get with the complete function. It will be called whether or not there is an error (network error or parsing error).

See http://api.jquery.com/jQuery.ajax/