you cannot use jquery.ajax to read chunked http response continuously. jquery ajax will call the success callback function only when connection terminates. You should use 
this  jquery plugin.
if you are using php then you can use this code:
 <html>
        <head>
            <script src="jquery-1.4.4.js"></script>
            <script src="jquery.stream-1.2.js"></script>
            <script>
                var println = function(string){
                    $("#console").append(string+"<br />");
                }
                $(document).ready(function(){
                    $.stream("stream.php",{
                        open:function(){
                            println("opened");
                        },
                        message:function(event){
                            println(event.data);
                        },
                        error:function(){
                            println("error");
                        },
                        close:function(){
                            println("closed");
                        }
                    });
                });
            </script>
        </head>
        <body>
            <div id="console"></div>
        </body>
    </html>
in the server side :
stream.php
<?php
   header('Content-Encoding', 'chunked');
   header('Transfer-Encoding', 'chunked');
   header('Content-Type', 'text/html');
   header('Connection', 'keep-alive');
   ob_flush();
   flush();
   echo("23123454645645646;");
   $p = "";
   for ($i=0; $i < 1024; $i++) { 
       $p .= " ";
   };
   echo($p.";");
   for ($i = 0; $i < 10000; $i++) {
      echo('6;string;');
      ob_flush();
      flush();
      sleep(2);
   }
?>