gistfile1.txt

sub vcl_recv {
   if (req.restarts == 0) {
       set req.http.x-magic = "0";
   }
   if (req.http.x-magic == "1") {
      set req.hash_always_miss = true;
   }
}

sub vcl_deliver {
    if (resp.http.content-length == "0" && req.http.x-magic == "0") {
         set req.http.x-magic = 1;
         return (restart);
    }
}