diff --git a/http_transport.go b/http_transport.go
index 396a680..37f756c 100644
--- a/http_transport.go
+++ b/http_transport.go
@@ -47,8 +47,12 @@ func (h *HTTPTransport) nextID() uint64 {
 	return h.nextid
 }
 
-// Call call a remote method
 func (h *HTTPTransport) Call(method string, args interface{}, reply interface{}) error {
+	return h.CallWithHeader(method, args, reply, nil)
+}
+
+// Call call a remote method
+func (h *HTTPTransport) CallWithHeader(method string, args interface{}, reply interface{}, header http.Header) error {
 	if args == nil {
 		args = []string{}
 	}
@@ -57,7 +61,7 @@ func (h *HTTPTransport) Call(method string, args interface{}, reply interface{})
 		Version: "2.0",
 		Method:  method,
 		Params:  args,
-		ID:      fmt.Sprintf("%d", h.nextID()),
+		ID:      h.nextID(),
 	}
 
 	data, err := json.Marshal(r)
@@ -74,6 +78,14 @@ func (h *HTTPTransport) Call(method string, args interface{}, reply interface{})
 		return err
 	}
 
+	if header != nil {
+		for k, v := range header {
+			for _, v1 := range v {
+				req.Header.Add(k, v1)
+			}
+		}
+	}
+
 	req.Header.Set("Content-Type", "application/json")
 
 	resp, err := h.Client.Do(req)