diff --git a/DMRNetwork.cpp b/DMRNetwork.cpp
index ea52096..91ae0a4 100644
--- a/DMRNetwork.cpp
+++ b/DMRNetwork.cpp
@@ -362,7 +362,7 @@ void CDMRNetwork::clock(unsigned int ms)
 	if (m_status == WAITING_CONNECT) {
 		m_retryTimer.clock(ms);
 		if (m_retryTimer.isRunning() && m_retryTimer.hasExpired()) {
-			bool ret = m_socket.open();
+			bool ret = m_socket.open(m_address.ss_family);
 			if (ret) {
 				ret = writeLogin();
 				if (!ret)
diff --git a/DStarNetwork.cpp b/DStarNetwork.cpp
index 295c289..072b7cf 100644
--- a/DStarNetwork.cpp
+++ b/DStarNetwork.cpp
@@ -68,7 +68,7 @@ bool CDStarNetwork::open()
 
 	m_pollTimer.start();
 
-	return m_socket.open();
+	return m_socket.open(m_address.ss_family);
 }
 
 bool CDStarNetwork::writeHeader(const unsigned char* header, unsigned int length, bool busy)
diff --git a/MMDVMHost.cpp b/MMDVMHost.cpp
index 4769895..9f792e5 100644
--- a/MMDVMHost.cpp
+++ b/MMDVMHost.cpp
@@ -336,7 +336,7 @@ int CMMDVMHost::run()
 		CUDPSocket::lookup(remoteAddress, remotePort, transparentAddress, transparentAddrLen);
 
 		transparentSocket = new CUDPSocket(localPort);
-		ret = transparentSocket->open();
+		ret = transparentSocket->open(transparentAddress.ss_family);
 		if (!ret) {
 			LogWarning("Could not open the Transparent data socket, disabling");
 			delete transparentSocket;
diff --git a/MobileGPS.cpp b/MobileGPS.cpp
index 7cd782e..0cb2c3b 100644
--- a/MobileGPS.cpp
+++ b/MobileGPS.cpp
@@ -43,7 +43,7 @@ CMobileGPS::~CMobileGPS()
 
 bool CMobileGPS::open()
 {
-	bool ret = m_socket.open();
+	bool ret = m_socket.open(m_address.ss_family);
 	if (!ret)
 		return false;
 
diff --git a/P25Network.cpp b/P25Network.cpp
index a326966..ed28fa6 100644
--- a/P25Network.cpp
+++ b/P25Network.cpp
@@ -110,7 +110,7 @@ bool CP25Network::open()
 	if (CUDPSocket::isnone(m_address))
 		return false;
 
-	return m_socket.open();
+	return m_socket.open(m_address.ss_family);
 }
 
 bool CP25Network::writeLDU1(const unsigned char* ldu1, const CP25Data& control, const CP25LowSpeedData& lsd, bool end)
diff --git a/RemoteCommand.cpp b/RemoteCommand.cpp
index 42a09be..9d7b038 100644
--- a/RemoteCommand.cpp
+++ b/RemoteCommand.cpp
@@ -61,15 +61,15 @@ CRemoteCommand::~CRemoteCommand()
 
 int CRemoteCommand::send(const std::string& command)
 {
-	CUDPSocket socket(0U);
-	
-	bool ret = socket.open();
-	if (!ret)
-		return 1;
-
 	sockaddr_storage address;
 	unsigned int addrlen;
-	CUDPSocket::lookup("localhost", m_port, address, addrlen);
+	CUDPSocket::lookup("127.0.0.1", m_port, address, addrlen);
+
+	CUDPSocket socket(0U);
+	
+	bool ret = socket.open(address.ss_family);
+	if (!ret)
+		return 1;
 
 	ret = socket.write((unsigned char*)command.c_str(), command.length(), address, addrlen);
 	if (!ret) {
diff --git a/RemoteControl.cpp b/RemoteControl.cpp
index 0c72f6b..0c29791 100644
--- a/RemoteControl.cpp
+++ b/RemoteControl.cpp
@@ -43,7 +43,7 @@ CRemoteControl::~CRemoteControl()
 
 bool CRemoteControl::open()
 {
-	return m_socket.open();
+	return m_socket.open(AF_INET);	/* XXX IPv4 only */
 }
 
 REMOTE_COMMAND CRemoteControl::getCommand()
diff --git a/UDPSocket.cpp b/UDPSocket.cpp
index 9e5e2cf..a2b5991 100644
--- a/UDPSocket.cpp
+++ b/UDPSocket.cpp
@@ -117,14 +117,37 @@ bool CUDPSocket::isnone(const sockaddr_storage &addr)
 		 (in->sin_addr.s_addr == htonl(INADDR_NONE)) );
 }
 
+bool CUDPSocket::open(const unsigned int af)
+{
+	switch (af) {
+	case AF_INET6:
+		m_address = "::";
+		break;
+	case AF_INET:
+		m_address = "0.0.0.0";
+		break;
+	default:
+		LogWarning("unknown address family - %d", af);
+		break;
+	}
+
+	return open();
+}
+
 bool CUDPSocket::open()
 {
 	int err;
 	sockaddr_storage addr;
 	unsigned int addrlen;
 
+	/* m_address should be defined */
+	if (m_address.empty()) {
+		LogError("The local address is undefined");
+		return false;
+	}
+
 	/* to determine protocol family, call lookup() first. */
-	err = lookup(m_address.empty() ? "0.0.0.0" : m_address.c_str(), m_port, addr, addrlen);
+	err = lookup(m_address.c_str(), m_port, addr, addrlen);
 	if (err) {
 		LogError("The local address is invalid - %s", m_address.c_str());
 		return false;
diff --git a/UDPSocket.h b/UDPSocket.h
index 288273f..b5add46 100644
--- a/UDPSocket.h
+++ b/UDPSocket.h
@@ -42,6 +42,7 @@ public:
 	~CUDPSocket();
 
 	bool open();
+	bool open(const unsigned int af);
 
 	int  read(unsigned char* buffer, unsigned int length, sockaddr_storage& address, unsigned int &address_length);
 	bool write(const unsigned char* buffer, unsigned int length, const sockaddr_storage& address, unsigned int address_length);