diff --git a/MQTTSNGateway/src/MQTTGWPublishHandler.cpp b/MQTTSNGateway/src/MQTTGWPublishHandler.cpp
index cbca3e7..9497414 100644
--- a/MQTTSNGateway/src/MQTTGWPublishHandler.cpp
+++ b/MQTTSNGateway/src/MQTTGWPublishHandler.cpp
@@ -49,6 +49,7 @@ void MQTTGWPublishHandler::handlePublish(Client* client, MQTTGWPacket* packet)
 
 	/* create MQTTSN_topicid */
 	MQTTSN_topicid topicId;
+	uint16_t id = 0;
 
 	if (pub.topiclen == 2)
 	{
@@ -61,11 +62,14 @@ void MQTTGWPublishHandler::handlePublish(Client* client, MQTTGWPacket* packet)
 		topicId.type = MQTTSN_TOPIC_TYPE_NORMAL;
 		topicId.data.long_.len = pub.topiclen;
 		topicId.data.long_.name = pub.topic;
-		unsigned short id = client->getTopics()->getTopicId(&topicId);
-		topicId.data.id = id;
+		id = client->getTopics()->getTopicId(&topicId);
 	}
 
-	if (topicId.data.id == 0)
+	if (id > 0)
+	{
+		topicId.data.id = id;
+	}
+	else
 	{
 		/* This message might be subscribed with wild card. */
 		Topic* topic = client->getTopics()->match(&topicId);
@@ -85,7 +89,7 @@ void MQTTGWPublishHandler::handlePublish(Client* client, MQTTGWPacket* packet)
 
 		/* add the Topic and get a TopicId */
 		topic = client->getTopics()->add(&topicId);
-		uint16_t id = topic->getTopicId();
+		id = topic->getTopicId();
 
 		if (id > 0)
 		{
diff --git a/MQTTSNGateway/src/MQTTSNGWBrokerRecvTask.cpp b/MQTTSNGateway/src/MQTTSNGWBrokerRecvTask.cpp
index 7701af8..5d093dc 100644
--- a/MQTTSNGateway/src/MQTTSNGWBrokerRecvTask.cpp
+++ b/MQTTSNGateway/src/MQTTSNGWBrokerRecvTask.cpp
@@ -136,7 +136,7 @@ void BrokerRecvTask::run(void)
 									client->getNetwork()->close();
 									delete packet;
 
-									/* delete client when the client is not authorized on & session is clean */
+									/* delete client when the client is not authorized & session is clean */
 									_gateway->getClientList()->erase(client);
 
 									if ( client )
diff --git a/MQTTSNGateway/src/MQTTSNGWClient.cpp b/MQTTSNGateway/src/MQTTSNGWClient.cpp
index 965e90e..93bee22 100644
--- a/MQTTSNGateway/src/MQTTSNGWClient.cpp
+++ b/MQTTSNGateway/src/MQTTSNGWClient.cpp
@@ -830,7 +830,7 @@ Topics::~Topics()
 	}
 }
 
-uint16_t Topics::getTopicId(MQTTSN_topicid* topicid)
+uint16_t Topics::getTopicId(const MQTTSN_topicid* topicid)
 {
 	if (topicid->type != MQTTSN_TOPIC_TYPE_NORMAL)
 	{
@@ -863,7 +863,7 @@ Topic* Topics::getTopic(uint16_t id)
 	return 0;
 }
 
-Topic* Topics::getTopic(MQTTSN_topicid* topicid)
+Topic* Topics::getTopic(const MQTTSN_topicid* topicid)
 {
 	Topic* p = _first;
 	while (p)
@@ -877,7 +877,7 @@ Topic* Topics::getTopic(MQTTSN_topicid* topicid)
 	return 0;
 }
 
-Topic* Topics::add(MQTTSN_topicid* topicid)
+Topic* Topics::add(const MQTTSN_topicid* topicid)
 {
 	Topic* topic;
 	uint16_t id = 0;
@@ -901,7 +901,7 @@ Topic* Topics::add(MQTTSN_topicid* topicid)
 }
 
 
-Topic* Topics::add(string* topicName)
+Topic* Topics::add(const string* topicName)
 {
 	Topic* topic = 0;
 
@@ -942,7 +942,7 @@ uint16_t Topics::getNextTopicId()
 	return ++_nextTopicId == 0xffff ? _nextTopicId += 2 : _nextTopicId;
 }
 
-Topic* Topics::match(MQTTSN_topicid* topicid)
+Topic* Topics::match(const MQTTSN_topicid* topicid)
 {
 	if (topicid->type != MQTTSN_TOPIC_TYPE_NORMAL)
 	{
diff --git a/MQTTSNGateway/src/MQTTSNGWClient.h b/MQTTSNGateway/src/MQTTSNGWClient.h
index c4012c7..76c5c11 100644
--- a/MQTTSNGateway/src/MQTTSNGWClient.h
+++ b/MQTTSNGateway/src/MQTTSNGWClient.h
@@ -127,13 +127,13 @@ class Topics
 public:
 	Topics();
 	~Topics();
-	Topic* add(MQTTSN_topicid* topicid);
-	Topic* add(string* topic);
-	uint16_t getTopicId(MQTTSN_topicid* topic);
+	Topic* add(const MQTTSN_topicid* topicid);
+	Topic* add(const string* topic);
+	uint16_t getTopicId(const MQTTSN_topicid* topic);
 	uint16_t getNextTopicId();
 	Topic* getTopic(uint16_t topicId);
-	Topic* getTopic(MQTTSN_topicid* topicid);
-	Topic* match(MQTTSN_topicid* topicid);
+	Topic* getTopic(const MQTTSN_topicid* topicid);
+	Topic* match(const MQTTSN_topicid* topicid);
 
 private:
 	uint16_t _nextTopicId;