diff --git a/src/classlib/local.cc b/src/classlib/local.cc
index 95c557c..bdeedd9 100644
--- a/src/classlib/local.cc
+++ b/src/classlib/local.cc
@@ -240,6 +240,8 @@
 					throw exception("Can't find symbol %s",call[f].name);
 			}
 
+			session::lock();
+
 			// Get Session handle, setup base callbacks
 			set_log_handler(loghandler);
 			set_trace_handler(tracehandler);
@@ -247,19 +249,36 @@
 
 			set_display_charset();
 
+			session::unlock();
+
 		}
 
 		virtual ~local()
 		{
+			session::lock();
+
+			debug("%s(%p,%p)",__FUNCTION__,this,this->hSession);
+			if(is_connected()) {
+				disconnect();
+			}
+
+			debug("%s(%p,%p)",__FUNCTION__,this,this->hSession);
 			try
 			{
 				static void	(*session_free)(H3270 *h) = (void (*)(H3270 *)) get_symbol("lib3270_session_free");
 
+				debug("%s(%p,%p)",__FUNCTION__,this,this->hSession);
+
 				if(session_free && this->hSession)
 					session_free(this->hSession);
+
+				this->hSession = 0;
+
 			}
 			catch(exception e) { }
 
+			session::unlock();
+
 		}
 
 		bool is_connected(void)
@@ -282,7 +301,11 @@
 
 		int connect(void)
 		{
-			return _connect(hSession,0);
+			session::lock();
+			int rc = _connect(hSession,0);
+			session::unlock();
+
+			return rc;
 		}
 
 		int set_url(const char *uri)
@@ -292,7 +315,11 @@
 
 		int disconnect(void)
 		{
-			return _disconnect(hSession);
+			session::lock();
+			int rc = _disconnect(hSession);
+			session::unlock();
+
+			return rc;
 		}
 
 		bool is_ready(void)
diff --git a/src/classlib/session.cc b/src/classlib/session.cc
index dc8fc0d..4b02373 100644
--- a/src/classlib/session.cc
+++ b/src/classlib/session.cc
@@ -43,7 +43,56 @@
 #endif // HAVE_SYSLOG
 
 #if __cplusplus < 201103L
+
 	#define nullptr	NULL
+
+	#ifdef _WIN32
+
+		#error Implementar
+
+	#else
+
+		class recursive_mutex {
+		private:
+			pthread_mutex_t           mtx;
+			pthread_mutexattr_t       mtxAttr;
+
+		public:
+			recursive_mutex() {
+
+				memset(&mtx,0,sizeof(mtx));
+				memset(&mtxAttr,0,sizeof(mtxAttr));
+
+				pthread_mutexattr_init(&mtxAttr);
+				pthread_mutexattr_settype(&mtxAttr, PTHREAD_MUTEX_RECURSIVE);
+				pthread_mutex_init(&mtx, &mtxAttr);
+			};
+
+			~recursive_mutex() {
+				pthread_mutex_destroy(&mtx);
+			};
+
+			void lock(void) {
+				pthread_mutex_lock(&mtx);
+			};
+
+			void unlock(void) {
+				pthread_mutex_unlock(&mtx);
+			};
+
+			bool try_lock(void) {
+				 return pthread_mutex_trylock(&mtx) == 0;
+			};
+		};
+
+
+
+	#endif // _WIN32
+
+#else
+
+	#include <recursive_mutex>
+
 #endif // !c11
 
 
@@ -94,6 +143,19 @@
 	session	* session::last							= nullptr;
 	session	* (*session::factory)(const char *name)	= nullptr;
 
+	static recursive_mutex	mtx;
+
+
+	void session::lock()
+	{
+		mtx.lock();
+	}
+
+	void session::unlock()
+	{
+		mtx.unlock();
+	}
+
 	void session::init()
 	{
 		trace("Loading %s objects",PACKAGE_NAME);
diff --git a/src/include/pw3270/class.h b/src/include/pw3270/class.h
index 2f62691..d5261a8 100644
--- a/src/include/pw3270/class.h
+++ b/src/include/pw3270/class.h
@@ -132,6 +132,9 @@
 		static void		  init();
 		static void		  deinit();
 
+		static void		  lock();
+		static void		  unlock();
+
 		// Factory methods and settings
 		static session	* start(const char *name = 0);
 		static session	* create(const char *name = 0) throw (std::exception);
diff --git a/src/java/main.cc b/src/java/main.cc
index b3eaf2c..feccc6a 100644
--- a/src/java/main.cc
+++ b/src/java/main.cc
@@ -76,10 +76,14 @@ JNIEXPORT jint JNICALL Java_pw3270_terminal_init__Ljava_lang_String_2(JNIEnv *en
 
 	try {
 
+		session::lock();
+
 		jlong handle = reinterpret_cast<jlong>(session::create(id));
 		env->SetLongField(obj, getHandleField(env, obj), handle);
 		env->ReleaseStringUTFChars( j_id, id);
 
+		session::unlock();
+
 	} catch(std::exception &e) {
 
 		env->ReleaseStringUTFChars( j_id, id);
@@ -95,13 +99,23 @@ JNIEXPORT jint JNICALL Java_pw3270_terminal_deinit(JNIEnv *env, jobject obj) {
 
 	try {
 
+		session::lock();
+
 		session *s = getHandle(env,obj);
 
+		trace("********************* Destruindo objeto %p",s);
+
 		if(s) {
+		trace("********************* Destruindo objeto %p",s);
 			delete s;
+		trace("********************* Destruindo objeto %p",s);
 		}
 
+		trace("********************* Destruindo objeto %p",s);
 		env->SetLongField(obj, getHandleField(env, obj), 0);
+		trace("********************* Destruindo objeto %p",s);
+
+		session::unlock();
 
 	} catch(std::exception &e) {
 
diff --git a/src/lib3270/session.c b/src/lib3270/session.c
index e7f7838..a1bcc76 100644
--- a/src/lib3270/session.c
+++ b/src/lib3270/session.c
@@ -97,13 +97,13 @@ void lib3270_session_free(H3270 *h)
 	if(h == default_session)
 		default_session = NULL;
 
-
 	// Release hostname info
 	release_pointer(h->host.current);
 	release_pointer(h->host.full);
 	release_pointer(h->host.srvc);
 	release_pointer(h->host.qualified);
 
+	trace("Releasing session %p",h);
 	lib3270_free(h);
 
 }
@@ -258,14 +258,10 @@ H3270 * lib3270_session_new(const char *model)
 
 	trace("%s - configured=%s",__FUNCTION__,default_session ? "Yes" : "No");
 
-	if(default_session)
-	{
-		// TODO (perry#5#): Allocate a new structure.
-		errno = EBUSY;
-		return lib3270_get_default_session_handle();
-	}
+	hSession = lib3270_malloc(sizeof(H3270));
 
-	hSession = default_session = lib3270_malloc(sizeof(H3270));
+	if(!default_session)
+		default_session = hSession;
 
 	lib3270_session_init(hSession, model, _( "bracket" ) );
 
--
libgit2 0.21.2