diff --git a/CMakeLists.txt b/CMakeLists.txt
index dd55d11..d435253 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,7 +1,7 @@
 # cmake global
 cmake_minimum_required(VERSION 2.8.12)
 
-set(PROJECT_VERSION "2.1.20")
+set(PROJECT_VERSION "2.1.21")
 if (${CMAKE_VERSION} VERSION_GREATER 3.0)
 	cmake_policy(SET CMP0042 OLD) 	# fix MACOSX_RPATH
 	cmake_policy(SET CMP0048 NEW) 	# allow VERSION argument in project()
diff --git a/libstratum/EthStratumClient.cpp b/libstratum/EthStratumClient.cpp
index d963c0e..0f7e72e 100644
--- a/libstratum/EthStratumClient.cpp
+++ b/libstratum/EthStratumClient.cpp
@@ -143,6 +143,7 @@ void EthStratumClient::disconnect()
 	if (m_verbose)
 		LogS << "Disconnecting from stratum server";
 	m_connected = false;
+
 	m_authorized = false;
 	m_running = false;
 	m_socket.close();
@@ -301,6 +302,11 @@ void EthStratumClient::submitWork(h256 _nonce, bytes _hash, bytes _challenge, ui
 
 	Json::Value msg;
 
+	if (!isConnected()) {
+		LogB << "Can't submit share: no stratum connection, or not subscribed";
+		return;
+	}
+
 	msg["id"] = 4;
 	msg["method"] = "mining.submit";
 	msg["params"].append("0x" + _nonce.hex());
@@ -339,7 +345,7 @@ bool EthStratumClient::isRunning()
 	return m_running; 
 }
 
-bool EthStratumClient::isConnected() 
+bool EthStratumClient::isConnected()
 { 
 	return m_connected && m_authorized; 
 }
diff --git a/libstratum/EthStratumClient.h b/libstratum/EthStratumClient.h
index 0f18663..4cc375a 100644
--- a/libstratum/EthStratumClient.h
+++ b/libstratum/EthStratumClient.h
@@ -67,7 +67,6 @@ class EthStratumClient
 	void readResponse(const boost::system::error_code& ec, std::size_t bytes_transferred);
 	void processReponse(Json::Value& responseObject);
 	void writeStratum(Json::Value _json);
-	void setWork(Json::Value params);
 	void work_timeout_handler(const boost::system::error_code& ec);
 	string streamBufToStr(boost::asio::streambuf &buff);
 	void logJson(Json::Value _json);
@@ -78,7 +77,7 @@ class EthStratumClient
 	string m_password;
 
 	bool m_authorized;	// we're subscribed to the pool
-	bool m_connected;	// this refers to a TCP connection
+	bool m_connected;		// this refers to a TCP connection
 	bool m_running;		// the Boost::Asio worker thread is running & listening
 
 	int	m_retries = 0;