AJAX w / jQuery无法从请求中获得预期的响应（或任何响应）

$.ajax({
    type: \"GET\",
    url: url_to_web_service,
    dataType: \"xml\",
    success: function (xml) {
        // the array of image source locations we\'ll build from the XML
        var thumbImgArray = new Array();

        // find every image source location and add it to the array
        $(xml).find(\"image_src_location\").each(function () {
            thumbImgArray.push($(this));
        });

        // update the scrollable thumbnail images using the new array of image source locations 
        updateScrollableThumbs($(xml).find(\"indicator\"), thumbImgArray);
    },
    error: function (xhr, err) {
        alert(\"AJAX error function invoked: \\n\\treadyState: \" + xhr.readyState + \"\\n\\tstatus: \" + xhr.status);
        $(\'.error\').html(\"responseText: \" + xhr.responseText);
    }
});

Response Headers
Server  Apache-Coyote/1.1
Content-Type    text/xml;charset=ISO-8859-1
Content-Language    en-US
Content-Length  1326
Date    Wed, 25 May 2011 16:02:19 GMT

Request Headers
Host    localhost:8080
User-Agent  Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2.17) Gecko/20110420 Firefox/3.6.17 ( .NET CLR 3.5.30729)
Accept  application/xml, text/xml, */*
Accept-Language en-us,en;q=0.5
Accept-Encoding gzip,deflate
Accept-Charset  ISO-8859-1,utf-8;q=0.7,*;q=0.7
Keep-Alive  115
Connection  keep-alive
Origin  null

XML Parsing Error: no element found Location: moz-nullprincipal:{a6fb7963-9b10-464c-a07d-c8e439b98f0d} Line Number 1, Column 1:

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