Ajuda Site Jairelton

function buscar(chave)
        {
                var text=document.getElementById("resultados");

                var state = ["uninitialize", "<img src='http://res.stddev.appstate.edu/cvs/*checkout*/fallout/convert/images/ajax-loader.gif?rev=1.1&conten
t-type=image/gif' />", "sent", "receiving", "loaded"];

                req = new XMLHttpRequest();

                req.open("GET", "http://localhost:8080/teste/testa-adiciona?chave="+chave,true);


                req.onreadystatechange = function()
                {
                 if (req.readyState < 4)
                 {
                    text.innerHTML = state[req.readyState] ;
                 }
                 else if (req.readyState == 4)
                 {
                                if(req.status==200)
                                {
                                        var xml = req.responseXML;
                                        montaTabela(xml);
                                }
                                else
                                {
                                        alert("Erro!");
                                }
                 }
                }
                req.send(null);
        }