diff --git a/libs/ysip/message.cpp b/libs/ysip/message.cpp
index 4c8d5698..9cf935b9 100644
--- a/libs/ysip/message.cpp
+++ b/libs/ysip/message.cpp
@@ -292,12 +292,21 @@ void SIPMessage::complete(SIPEngine* engine, const char* user, const char* domai
 	addHeader("Call-ID",tmp);
     }
 
-    if (!(isAnswer() || getHeader("CSeq"))) {
-	String tmp;
-	if (m_cseq <= 0)
-	    m_cseq = engine->getNextCSeq();
-	tmp << m_cseq << " " << method;
-	addHeader("CSeq",tmp);
+    if (!isAnswer()) {
+	hl = const_cast<MimeHeaderLine*>(getHeader("CSeq"));
+	if (hl) {
+	    if (m_cseq <= 0) {
+		String tmp(*hl);
+		tmp >> m_cseq;
+	    }
+	}
+	else {
+	    String tmp;
+	    if (m_cseq <= 0)
+		m_cseq = engine->getNextCSeq();
+	    tmp << m_cseq << " " << method;
+	    addHeader("CSeq",tmp);
+	}
     }
 
     const char* info = isAnswer() ? "Server" : "User-Agent";
diff --git a/modules/ysipchan.cpp b/modules/ysipchan.cpp
index 5b47c2b9..2c4b0d65 100644
--- a/modules/ysipchan.cpp
+++ b/modules/ysipchan.cpp
@@ -932,6 +932,7 @@ public:
     virtual bool msgText(Message& msg, const char* text);
     virtual bool msgDrop(Message& msg, const char* reason);
     virtual bool msgUpdate(Message& msg);
+    virtual bool msgControl(Message& msg);
     virtual bool callRouted(Message& msg);
     virtual void callAccept(Message& msg);
     virtual void callRejected(const char* error, const char* reason, const Message* msg);
@@ -6013,6 +6014,7 @@ YateSIPConnection::YateSIPConnection(Message& msg, const String& uri, const char
     filterDebug(m_address);
     m_dialog = *m;
     m_dialog.localCSeq = m->getCSeq();
+    m_dialog.remoteCSeq = msg.getIntValue("remote_cseq",-1);
     if (s_privacy)
 	copyPrivacy(*m,msg);
 
@@ -7529,6 +7531,31 @@ bool YateSIPConnection::msgUpdate(Message& msg)
     return false;
 }
 
+bool YateSIPConnection::msgControl(Message& msg)
+{
+    bool ok = false;
+    if (msg[YSTRING("operation")] == YSTRING("query")) {
+	msg.setParam("sip_uri",m_uri);
+	msg.setParam("sip_callid",callid());
+	String tmp;
+	tmp << "<" << m_dialog.localURI << ">";
+	if (m_dialog.localTag)
+	    tmp << ";tag=" << m_dialog.localTag;
+	msg.setParam("sip_from",tmp);
+	tmp.clear();
+	tmp << "<" << m_dialog.remoteURI << ">";
+	if (m_dialog.remoteTag)
+	    tmp << ";tag=" << m_dialog.remoteTag;
+	msg.setParam("sip_to",tmp);
+	if (m_dialog.localCSeq >= 0)
+	    msg.setParam("local_cseq",String(m_dialog.localCSeq));
+	if (m_dialog.remoteCSeq >= 0)
+	    msg.setParam("remote_cseq",String(m_dialog.remoteCSeq));
+	ok = true;
+    }
+    return Channel::msgControl(msg) || ok;
+}
+
 void YateSIPConnection::endDisconnect(const Message& msg, bool handled)
 {
     const String* reason = msg.getParam(YSTRING("reason"));