diff --git a/xmpp/iot/control.go b/xmpp/iot/control.go
index 16908cc..20c384d 100644
--- a/xmpp/iot/control.go
+++ b/xmpp/iot/control.go
@@ -2,16 +2,6 @@ package iot
 
 import "encoding/xml"
 
-/*
-type Control struct {
-	ControlSet     ControlSet     `xml:",omitempty"`
-	ControlGetForm ControlGetForm `xml:",omitempty"`
-}
-
-func (*Control) IQPayload() {
-}
-*/
-
 type ControlSet struct {
 	XMLName xml.Name       `xml:"urn:xmpp:iot:control set"`
 	Fields  []ControlField `xml:",any"`
@@ -29,3 +19,10 @@ type ControlField struct {
 	Name    string `xml:"name,attr,omitempty"`
 	Value   string `xml:"value,attr,omitempty"`
 }
+
+type ControlSetResponse struct {
+	XMLName xml.Name `xml:"urn:xmpp:iot:control setResponse"`
+}
+
+func (*ControlSetResponse) IsIQPayload() {
+}
diff --git a/xmpp/iq.go b/xmpp/iq.go
index 1ecabf5..a0c5cf2 100644
--- a/xmpp/iq.go
+++ b/xmpp/iq.go
@@ -2,6 +2,7 @@ package xmpp
 
 import (
 	"encoding/xml"
+	"fmt"
 
 	"github.com/processone/gox/xmpp/iot"
 )
@@ -73,3 +74,22 @@ func (iq *ClientIQ) UnmarshalXML(d *xml.Decoder, start xml.StartElement) error {
 		}
 	}
 }
+
+func (iq *ClientIQ) XMPPFormat() string {
+	if iq.Payload != nil {
+		var payload []byte
+		var err error
+		if payload, err = xml.Marshal(iq.Payload); err != nil {
+			return fmt.Sprintf("<iq to='%s' type='%s' id='%s' xml:lang='en'>"+
+				"</iq>",
+				iq.To, iq.Type, iq.Id)
+		}
+		return fmt.Sprintf("<iq to='%s' type='%s' id='%s' xml:lang='en'>"+
+			"%s</iq>",
+			iq.To, iq.Type, iq.Id, payload)
+	}
+	return fmt.Sprintf("<iq to='%s' type='%s' id='%s' xml:lang='en'>"+
+		"%s</iq>",
+		iq.To, iq.Type, iq.Id,
+		iq.RawXML)
+}