jquery取xml的问题（高分）

package com.lovo.servlet;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
 * 功能:处理创建问题和答案
 * @author zuoli
 * version v1.0
 * date 08/05/27
 *
 */
public class Test extends HttpServlet{

protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
request.setCharacterEncoding("gbk");
response.setContentType("text/xml;charset=gbk");
PrintWriter out = response.getWriter();
out.write("<?xml version=1.0 encoding=GBK?>");
out.write("<body>");
out.write("tt");
out.write("</body>");
} protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.doGet(request, response);
}
}
$(function(){
$.ajax({
url:"/myoa/test",
type:"get",
dataType:"xml",
complete:function(xml){
alert($(xml).find("option").text());
alert($(xml).find("tt").text());
}
});
})
弹出空值杂办呢，搞了很好没搞定，