diff --git a/common/JackAudioDriver.cpp b/common/JackAudioDriver.cpp
index 3bcae9e9..dc53077c 100644
--- a/common/JackAudioDriver.cpp
+++ b/common/JackAudioDriver.cpp
@@ -101,7 +101,6 @@ int JackAudioDriver::Attach()
     jack_port_id_t port_index;
     char name[JACK_CLIENT_NAME_SIZE + JACK_PORT_NAME_SIZE];
     char alias[JACK_CLIENT_NAME_SIZE + JACK_PORT_NAME_SIZE];
-    unsigned long port_flags = JackPortIsOutput | JackPortIsPhysical | JackPortIsTerminal;
     int i;
 
     jack_log("JackAudioDriver::Attach fBufferSize = %ld fSampleRate = %ld", fEngineControl->fBufferSize, fEngineControl->fSampleRate);
@@ -109,7 +108,7 @@ int JackAudioDriver::Attach()
     for (i = 0; i < fCaptureChannels; i++) {
         snprintf(alias, sizeof(alias) - 1, "%s:%s:out%d", fAliasName, fCaptureDriverName, i + 1);
         snprintf(name, sizeof(name) - 1, "%s:capture_%d", fClientControl.fName, i + 1);
-        if ((port_index = fGraphManager->AllocatePort(fClientControl.fRefNum, name, JACK_DEFAULT_AUDIO_TYPE, (JackPortFlags)port_flags, fEngineControl->fBufferSize)) == NO_PORT) {
+        if ((port_index = fGraphManager->AllocatePort(fClientControl.fRefNum, name, JACK_DEFAULT_AUDIO_TYPE, CaptureDriverFlags, fEngineControl->fBufferSize)) == NO_PORT) {
             jack_error("driver: cannot register port for %s", name);
             return -1;
         }
@@ -120,12 +119,10 @@ int JackAudioDriver::Attach()
         jack_log("JackAudioDriver::Attach fCapturePortList[i] port_index = %ld", port_index);
     }
 
-    port_flags = JackPortIsInput | JackPortIsPhysical | JackPortIsTerminal;
-
     for (i = 0; i < fPlaybackChannels; i++) {
         snprintf(alias, sizeof(alias) - 1, "%s:%s:in%d", fAliasName, fPlaybackDriverName, i + 1);
         snprintf(name, sizeof(name) - 1, "%s:playback_%d", fClientControl.fName, i + 1);
-        if ((port_index = fGraphManager->AllocatePort(fClientControl.fRefNum, name, JACK_DEFAULT_AUDIO_TYPE, (JackPortFlags)port_flags, fEngineControl->fBufferSize)) == NO_PORT) {
+        if ((port_index = fGraphManager->AllocatePort(fClientControl.fRefNum, name, JACK_DEFAULT_AUDIO_TYPE, PlaybackDriverFlags, fEngineControl->fBufferSize)) == NO_PORT) {
             jack_error("driver: cannot register port for %s", name);
             return -1;
         }
diff --git a/common/JackDriver.h b/common/JackDriver.h
index 83f7e250..901e6bf3 100644
--- a/common/JackDriver.h
+++ b/common/JackDriver.h
@@ -109,6 +109,10 @@ class SERVER_EXPORT JackDriverClientInterface : public JackDriverInterface, publ
 /*!
  \brief The base class for drivers.
  */
+ 
+#define CaptureDriverFlags  static_cast<JackPortFlags>(JackPortIsOutput | JackPortIsPhysical | JackPortIsTerminal | JackPortIsActive)
+#define PlaybackDriverFlags static_cast<JackPortFlags>(JackPortIsInput | JackPortIsPhysical | JackPortIsTerminal | JackPortIsActive)
+#define MonitorDriverFlags static_cast<JackPortFlags>(JackPortIsOutput | JackPortIsActive)
 
 class SERVER_EXPORT JackDriver : public JackDriverClientInterface
 {
diff --git a/common/JackEngine.cpp b/common/JackEngine.cpp
index 4dc1967f..8c205975 100644
--- a/common/JackEngine.cpp
+++ b/common/JackEngine.cpp
@@ -651,7 +651,30 @@ int JackEngine::ClientActivate(int refnum, bool is_real_time)
         jack_error("JackEngine::ClientActivate wait error ref = %ld name = %s", refnum, client->GetClientControl()->fName);
         return -1;
     } else {
+        jack_int_t input_ports[PORT_NUM_FOR_CLIENT];
+        jack_int_t output_ports[PORT_NUM_FOR_CLIENT];
+        fGraphManager->GetInputPorts(refnum, input_ports);
+        fGraphManager->GetOutputPorts(refnum, output_ports);
+        
+        // First add port state to JackPortIsActive
+        for (int i = 0; (i < PORT_NUM_FOR_CLIENT) && (input_ports[i] != EMPTY); i++) {
+            fGraphManager->ActivatePort(input_ports[i]);
+        }
+        for (int i = 0; (i < PORT_NUM_FOR_CLIENT) && (output_ports[i] != EMPTY); i++) {
+            fGraphManager->ActivatePort(output_ports[i]);
+        }
+        
+        // Notify client
         NotifyActivate(refnum);
+        
+        // Then issue port registration notification
+        for (int i = 0; (i < PORT_NUM_FOR_CLIENT) && (input_ports[i] != EMPTY); i++) {
+            NotifyPortRegistation(input_ports[i], true);
+        }
+        for (int i = 0; (i < PORT_NUM_FOR_CLIENT) && (output_ports[i] != EMPTY); i++) {
+            NotifyPortRegistation(output_ports[i], true);
+        }
+
         return 0;
     }
 }
@@ -662,18 +685,27 @@ int JackEngine::ClientDeactivate(int refnum)
     JackClientInterface* client = fClientTable[refnum];
     jack_log("JackEngine::ClientDeactivate ref = %ld name = %s", refnum, client->GetClientControl()->fName);
 
-    // Disconnect all ports ==> notifications are sent
-    jack_int_t ports[PORT_NUM_FOR_CLIENT];
-    int i;
+    jack_int_t input_ports[PORT_NUM_FOR_CLIENT];
+    jack_int_t output_ports[PORT_NUM_FOR_CLIENT];
+    fGraphManager->GetInputPorts(refnum, input_ports);
+    fGraphManager->GetOutputPorts(refnum, output_ports);
 
-    fGraphManager->GetInputPorts(refnum, ports);
-    for (i = 0; (i < PORT_NUM_FOR_CLIENT) && (ports[i] != EMPTY) ; i++) {
-        PortDisconnect(refnum, ports[i], ALL_PORTS);
+    // First disconnect all ports and remove their JackPortIsActive state
+    for (int i = 0; (i < PORT_NUM_FOR_CLIENT) && (input_ports[i] != EMPTY); i++) {
+        PortDisconnect(refnum, input_ports[i], ALL_PORTS);
+        fGraphManager->DeactivatePort(input_ports[i]);
     }
-
-    fGraphManager->GetOutputPorts(refnum, ports);
-    for (i = 0; (i < PORT_NUM_FOR_CLIENT) && (ports[i] != EMPTY) ; i++) {
-        PortDisconnect(refnum, ports[i], ALL_PORTS);
+    for (int i = 0; (i < PORT_NUM_FOR_CLIENT) && (output_ports[i] != EMPTY); i++) {
+        PortDisconnect(refnum, output_ports[i], ALL_PORTS);
+        fGraphManager->DeactivatePort(output_ports[i]);
+    }
+    
+    // Then issue port registration notification
+    for (int i = 0; (i < PORT_NUM_FOR_CLIENT) && (input_ports[i] != EMPTY); i++) {
+        NotifyPortRegistation(input_ports[i], false);
+    }
+    for (int i = 0; (i < PORT_NUM_FOR_CLIENT) && (output_ports[i] != EMPTY); i++) {
+        NotifyPortRegistation(output_ports[i], false);
     }
 
     fGraphManager->Deactivate(refnum);
@@ -695,7 +727,8 @@ int JackEngine::ClientDeactivate(int refnum)
 int JackEngine::PortRegister(int refnum, const char* name, const char *type, unsigned int flags, unsigned int buffer_size, jack_port_id_t* port_index)
 {
     jack_log("JackEngine::PortRegister ref = %ld name = %s type = %s flags = %d buffer_size = %d", refnum, name, type, flags, buffer_size);
- 
+    JackClientInterface* client = fClientTable[refnum];
+
     // Check if port name already exists
     if (fGraphManager->GetPort(name) != NO_PORT) {
         jack_error("port_name \"%s\" already exists", name);
@@ -704,7 +737,8 @@ int JackEngine::PortRegister(int refnum, const char* name, const char *type, uns
 
     *port_index = fGraphManager->AllocatePort(refnum, name, type, (JackPortFlags)flags, fEngineControl->fBufferSize);
     if (*port_index != NO_PORT) {
-        NotifyPortRegistation(*port_index, true);
+        if (client->GetClientControl()->fActive)
+            NotifyPortRegistation(*port_index, true);
         return 0;
     } else {
         return -1;
@@ -714,12 +748,14 @@ int JackEngine::PortRegister(int refnum, const char* name, const char *type, uns
 int JackEngine::PortUnRegister(int refnum, jack_port_id_t port_index)
 {
     jack_log("JackEngine::PortUnRegister ref = %ld port_index = %ld", refnum, port_index);
- 
+    JackClientInterface* client = fClientTable[refnum];
+
     // Disconnect port ==> notification is sent
     PortDisconnect(refnum, port_index, ALL_PORTS);
 
     if (fGraphManager->ReleasePort(refnum, port_index) == 0) {
-        NotifyPortRegistation(port_index, false);
+        if (client->GetClientControl()->fActive)
+            NotifyPortRegistation(port_index, false);
         return 0;
     } else {
         return -1;
diff --git a/common/JackGraphManager.cpp b/common/JackGraphManager.cpp
index ce77f875..36e29430 100644
--- a/common/JackGraphManager.cpp
+++ b/common/JackGraphManager.cpp
@@ -376,6 +376,18 @@ int JackGraphManager::ReleasePort(int refnum, jack_port_id_t port_index)
     return res;
 }
 
+void JackGraphManager::ActivatePort(jack_port_id_t port_index)
+{
+    JackPort* port = GetPort(port_index);
+    port->fFlags = (JackPortFlags)(port->fFlags | JackPortIsActive);
+}
+
+void JackGraphManager::DeactivatePort(jack_port_id_t port_index)
+{
+    JackPort* port = GetPort(port_index);
+    port->fFlags = (JackPortFlags)(port->fFlags | ~JackPortIsActive);
+}
+
 void JackGraphManager::GetInputPorts(int refnum, jack_int_t* res)
 {
     JackConnectionManager* manager = WriteNextStateStart();
diff --git a/common/JackGraphManager.h b/common/JackGraphManager.h
index c2d7e105..93b09ff9 100644
--- a/common/JackGraphManager.h
+++ b/common/JackGraphManager.h
@@ -65,6 +65,8 @@ class SERVER_EXPORT JackGraphManager : public JackShmMem, public JackAtomicState
         // Ports management
         jack_port_id_t AllocatePort(int refnum, const char* port_name, const char* port_type, JackPortFlags flags, jack_nframes_t buffer_size);
         int ReleasePort(int refnum, jack_port_id_t port_index);
+        void ActivatePort(jack_port_id_t port_index);
+        void DeactivatePort(jack_port_id_t port_index);
         void GetInputPorts(int refnum, jack_int_t* res);
         void GetOutputPorts(int refnum, jack_int_t* res);
         void RemoveAllPorts(int refnum);
@@ -75,7 +77,7 @@ class SERVER_EXPORT JackGraphManager : public JackShmMem, public JackAtomicState
         int ComputeTotalLatency(jack_port_id_t port_index);
         int ComputeTotalLatencies();
         int RequestMonitor(jack_port_id_t port_index, bool onoff);
-
+   
         // Connections management
         int Connect(jack_port_id_t src_index, jack_port_id_t dst_index);
         int Disconnect(jack_port_id_t src_index, jack_port_id_t dst_index);
diff --git a/common/JackMidiDriver.cpp b/common/JackMidiDriver.cpp
index b5bfd4c4..4ddf417c 100644
--- a/common/JackMidiDriver.cpp
+++ b/common/JackMidiDriver.cpp
@@ -74,7 +74,6 @@ int JackMidiDriver::Attach()
     jack_port_id_t port_index;
     char name[JACK_CLIENT_NAME_SIZE + JACK_PORT_NAME_SIZE];
     char alias[JACK_CLIENT_NAME_SIZE + JACK_PORT_NAME_SIZE];
-    unsigned long port_flags = JackPortIsOutput | JackPortIsPhysical | JackPortIsTerminal;
     int i;
 
     jack_log("JackMidiDriver::Attach fBufferSize = %ld fSampleRate = %ld", fEngineControl->fBufferSize, fEngineControl->fSampleRate);
@@ -82,7 +81,7 @@ int JackMidiDriver::Attach()
     for (i = 0; i < fCaptureChannels; i++) {
         snprintf(alias, sizeof(alias) - 1, "%s:%s:out%d", fAliasName, fCaptureDriverName, i + 1);
         snprintf(name, sizeof(name) - 1, "%s:capture_%d", fClientControl.fName, i + 1);
-        if ((port_index = fGraphManager->AllocatePort(fClientControl.fRefNum, name, JACK_DEFAULT_MIDI_TYPE, (JackPortFlags)port_flags, fEngineControl->fBufferSize)) == NO_PORT) {
+        if ((port_index = fGraphManager->AllocatePort(fClientControl.fRefNum, name, JACK_DEFAULT_MIDI_TYPE, CaptureDriverFlags, fEngineControl->fBufferSize)) == NO_PORT) {
             jack_error("driver: cannot register port for %s", name);
             return -1;
         }
@@ -92,12 +91,10 @@ int JackMidiDriver::Attach()
         jack_log("JackMidiDriver::Attach fCapturePortList[i] port_index = %ld", port_index);
     }
 
-    port_flags = JackPortIsInput | JackPortIsPhysical | JackPortIsTerminal;
-
     for (i = 0; i < fPlaybackChannels; i++) {
         snprintf(alias, sizeof(alias) - 1, "%s:%s:in%d", fAliasName, fPlaybackDriverName, i + 1);
         snprintf(name, sizeof(name) - 1, "%s:playback_%d", fClientControl.fName, i + 1);
-        if ((port_index = fGraphManager->AllocatePort(fClientControl.fRefNum, name, JACK_DEFAULT_MIDI_TYPE, (JackPortFlags)port_flags, fEngineControl->fBufferSize)) == NO_PORT) {
+        if ((port_index = fGraphManager->AllocatePort(fClientControl.fRefNum, name, JACK_DEFAULT_MIDI_TYPE, PlaybackDriverFlags, fEngineControl->fBufferSize)) == NO_PORT) {
             jack_error("driver: cannot register port for %s", name);
             return -1;
         }
diff --git a/common/JackNetOneDriver.cpp b/common/JackNetOneDriver.cpp
index 4a75cc23..3259b563 100644
--- a/common/JackNetOneDriver.cpp
+++ b/common/JackNetOneDriver.cpp
@@ -138,19 +138,15 @@ namespace Jack
 	jack_port_id_t port_id;
 	char buf[64];
 	unsigned int chn;
-	int port_flags;
-
 
 	//if (netj.handle_transport_sync)
 	//    jack_set_sync_callback(netj.client, (JackSyncCallback) net_driver_sync_cb, NULL);
 
-	port_flags = JackPortIsOutput | JackPortIsPhysical | JackPortIsTerminal;
-
 	for (chn = 0; chn < netj.capture_channels_audio; chn++) {
 	    snprintf (buf, sizeof(buf) - 1, "system:capture_%u", chn + 1);
 
             if ( ( port_id = fGraphManager->AllocatePort ( fClientControl.fRefNum, buf, JACK_DEFAULT_AUDIO_TYPE,
-                             static_cast<JackPortFlags> ( port_flags ), fEngineControl->fBufferSize ) ) == NO_PORT )
+                             CaptureDriverFlags, fEngineControl->fBufferSize ) ) == NO_PORT )
             {
                 jack_error ( "driver: cannot register port for %s", buf );
                 return -1;
@@ -184,7 +180,7 @@ namespace Jack
 	    snprintf (buf, sizeof(buf) - 1, "system:capture_%u", chn + 1);
 
             if ( ( port_id = fGraphManager->AllocatePort ( fClientControl.fRefNum, buf, JACK_DEFAULT_MIDI_TYPE,
-                             static_cast<JackPortFlags> ( port_flags ), fEngineControl->fBufferSize ) ) == NO_PORT )
+                             CaptureDriverFlags, fEngineControl->fBufferSize ) ) == NO_PORT )
             {
                 jack_error ( "driver: cannot register port for %s", buf );
                 return -1;
@@ -195,13 +191,11 @@ namespace Jack
 		jack_slist_append (netj.capture_ports, (void *)(intptr_t)port_id);
 	}
 
-	port_flags = JackPortIsInput | JackPortIsPhysical | JackPortIsTerminal;
-
 	for (chn = 0; chn < netj.playback_channels_audio; chn++) {
 	    snprintf (buf, sizeof(buf) - 1, "system:playback_%u", chn + 1);
 
             if ( ( port_id = fGraphManager->AllocatePort ( fClientControl.fRefNum, buf, JACK_DEFAULT_AUDIO_TYPE,
-                             static_cast<JackPortFlags> ( port_flags ), fEngineControl->fBufferSize ) ) == NO_PORT )
+                             PlaybackDriverFlags, fEngineControl->fBufferSize ) ) == NO_PORT )
             {
                 jack_error ( "driver: cannot register port for %s", buf );
                 return -1;
@@ -231,7 +225,7 @@ namespace Jack
 	    snprintf (buf, sizeof(buf) - 1, "system:playback_%u", chn + 1);
 
             if ( ( port_id = fGraphManager->AllocatePort ( fClientControl.fRefNum, buf, JACK_DEFAULT_MIDI_TYPE,
-                             static_cast<JackPortFlags> ( port_flags ), fEngineControl->fBufferSize ) ) == NO_PORT )
+                             PlaybackDriverFlags, fEngineControl->fBufferSize ) ) == NO_PORT )
             {
                 jack_error ( "driver: cannot register port for %s", buf );
                 return -1;
diff --git a/common/jack/types.h b/common/jack/types.h
index 6c1b0f95..3722d7f4 100644
--- a/common/jack/types.h
+++ b/common/jack/types.h
@@ -295,7 +295,15 @@ enum JackPortFlags {
      * systems are examples of clients that would set this flag for
      * their ports.
      */
-    JackPortIsTerminal = 0x10
+    JackPortIsTerminal = 0x10,
+    
+    /**
+     * JackPortIsActive means the port has been registered and the 
+     * client is "active", that is jack_activate has been called
+     * 
+     * JackPortIsActive is on between jack_activate and jack_deactivate.
+     */
+    JackPortIsActive = 0x20
 };
 
 /**
diff --git a/example-clients/lsp.c b/example-clients/lsp.c
index db8b4543..5a3362f2 100644
--- a/example-clients/lsp.c
+++ b/example-clients/lsp.c
@@ -208,6 +208,12 @@ main (int argc, char *argv[])
 				if (flags & JackPortIsTerminal) {
 					fputs ("terminal,", stdout);
 				}
+                
+                if (flags & JackPortIsActive) {
+                    fputs ("active,", stdout);
+                } else {
+                    fputs ("non-active,", stdout);
+                }
 				putc ('\n', stdout);
 			}
 		}
diff --git a/linux/alsa/JackAlsaDriver.cpp b/linux/alsa/JackAlsaDriver.cpp
index 8c0168e5..fff7aea9 100644
--- a/linux/alsa/JackAlsaDriver.cpp
+++ b/linux/alsa/JackAlsaDriver.cpp
@@ -2087,7 +2087,7 @@ int JackAlsaDriver::Attach()
     assert(fCaptureChannels < DRIVER_PORT_NUM);
     assert(fPlaybackChannels < DRIVER_PORT_NUM);
 
-    port_flags = JackPortIsOutput | JackPortIsPhysical | JackPortIsTerminal;
+    port_flags = (unsigned long)CaptureDriverFlags;
 
     alsa_driver_t* alsa_driver = (alsa_driver_t*)fDriver;
 
@@ -2114,7 +2114,7 @@ int JackAlsaDriver::Attach()
         jack_log("JackAudioDriver::Attach fCapturePortList[i] %ld ", port_index);
     }
 
-    port_flags = JackPortIsInput | JackPortIsPhysical | JackPortIsTerminal;
+    port_flags = (unsigned long)PlaybackDriverFlags;
 
     for (int i = 0; i < fPlaybackChannels; i++) {
         snprintf(alias, sizeof(alias) - 1, "%s:playback_%u", fAliasName, i + 1);
@@ -2135,7 +2135,7 @@ int JackAlsaDriver::Attach()
         if (fWithMonitorPorts) {
             jack_log("Create monitor port ");
             snprintf(name, sizeof(name) - 1, "%s:monitor_%d", fClientControl.fName, i + 1);
-            if ((port_index = fGraphManager->AllocatePort(fClientControl.fRefNum, name, JACK_DEFAULT_AUDIO_TYPE, JackPortIsOutput, fEngineControl->fBufferSize)) == NO_PORT) {
+            if ((port_index = fGraphManager->AllocatePort(fClientControl.fRefNum, name, JACK_DEFAULT_AUDIO_TYPE, MonitorDriverFlags, fEngineControl->fBufferSize)) == NO_PORT) {
                 jack_error ("ALSA: cannot register monitor port for %s", name);
             } else {
                 port = fGraphManager->GetPort(port_index);
diff --git a/linux/alsa/alsa_rawmidi.c b/linux/alsa/alsa_rawmidi.c
index 13d7f310..62e18cd7 100644
--- a/linux/alsa/alsa_rawmidi.c
+++ b/linux/alsa/alsa_rawmidi.c
@@ -432,7 +432,7 @@ inline int midi_port_open_jack(alsa_rawmidi_t *midi, midi_port_t *port, int type
 		snprintf(name, sizeof(name) - 1, "system:midi_playback_%d", ++midi->midi_out_cnt);
 
 	port->jack = jack_port_register(midi->client, name, JACK_DEFAULT_MIDI_TYPE,
-		type | JackPortIsPhysical|JackPortIsTerminal, 0);
+		type | JackPortIsPhysical | JackPortIsTerminal | JackPortIsActive, 0);
 		
 	if (port->jack) 
 		jack_port_set_alias(port->jack, alias);
diff --git a/linux/alsa/alsa_seqmidi.c b/linux/alsa/alsa_seqmidi.c
index f079703c..0abc52a9 100644
--- a/linux/alsa/alsa_seqmidi.c
+++ b/linux/alsa/alsa_seqmidi.c
@@ -488,7 +488,7 @@ port_t* port_create(alsa_seqmidi_t *self, int type, snd_seq_addr_t addr, const s
 	/* mark anything that looks like a hardware port as physical&terminal */
 
 	if (snd_seq_port_info_get_type (info) & (SND_SEQ_PORT_TYPE_HARDWARE|SND_SEQ_PORT_TYPE_PORT|SND_SEQ_PORT_TYPE_SPECIFIC)) {
-		jack_caps |= (JackPortIsPhysical|JackPortIsTerminal);
+		jack_caps |= (JackPortIsPhysical | JackPortIsTerminal | JackPortIsActive);
 	}
 
 	if (jack_caps & JackPortIsOutput)
diff --git a/linux/firewire/JackFFADODriver.cpp b/linux/firewire/JackFFADODriver.cpp
index 84487ae9..88d9baf7 100644
--- a/linux/firewire/JackFFADODriver.cpp
+++ b/linux/firewire/JackFFADODriver.cpp
@@ -359,8 +359,6 @@ int JackFFADODriver::Attach()
 {
     JackPort* port;
     int port_index;
-    unsigned long port_flags;
-
     char buf[JACK_PORT_NAME_SIZE];
     char portname[JACK_PORT_NAME_SIZE];
 
@@ -418,8 +416,6 @@ int JackFFADODriver::Attach()
     /* ports */
 
     // capture
-    port_flags = JackPortIsOutput | JackPortIsPhysical | JackPortIsTerminal;
-
     driver->capture_nchannels = ffado_streaming_get_nb_capture_streams(driver->dev);
     driver->capture_channels = (ffado_capture_channel_t *)calloc(driver->capture_nchannels, sizeof(ffado_capture_channel_t));
     if (driver->capture_channels == NULL) {
@@ -437,7 +433,7 @@ int JackFFADODriver::Attach()
             printMessage ("Registering audio capture port %s", buf);
             if ((port_index = fGraphManager->AllocatePort(fClientControl.fRefNum, buf,
                               JACK_DEFAULT_AUDIO_TYPE,
-                              (JackPortFlags)port_flags,
+                              CaptureDriverFlags,
                               fEngineControl->fBufferSize)) == NO_PORT) {
                 jack_error("driver: cannot register port for %s", buf);
                 return -1;
@@ -460,7 +456,7 @@ int JackFFADODriver::Attach()
             printMessage ("Registering midi capture port %s", buf);
             if ((port_index = fGraphManager->AllocatePort(fClientControl.fRefNum, buf,
                               JACK_DEFAULT_MIDI_TYPE,
-                              (JackPortFlags)port_flags,
+                              CaptureDriverFlags,
                               fEngineControl->fBufferSize)) == NO_PORT) {
                 jack_error("driver: cannot register port for %s", buf);
                 return -1;
@@ -489,8 +485,6 @@ int JackFFADODriver::Attach()
     }
 
     // playback
-    port_flags = JackPortIsInput | JackPortIsPhysical | JackPortIsTerminal;
-
     driver->playback_nchannels = ffado_streaming_get_nb_playback_streams(driver->dev);
     driver->playback_channels = (ffado_playback_channel_t *)calloc(driver->playback_nchannels, sizeof(ffado_playback_channel_t));
     if (driver->playback_channels == NULL) {
@@ -509,7 +503,7 @@ int JackFFADODriver::Attach()
             printMessage ("Registering audio playback port %s", buf);
             if ((port_index = fGraphManager->AllocatePort(fClientControl.fRefNum, buf,
                               JACK_DEFAULT_AUDIO_TYPE,
-                              (JackPortFlags)port_flags,
+                              PlaybackDriverFlags,
                               fEngineControl->fBufferSize)) == NO_PORT) {
                 jack_error("driver: cannot register port for %s", buf);
                 return -1;
@@ -534,7 +528,7 @@ int JackFFADODriver::Attach()
             printMessage ("Registering midi playback port %s", buf);
             if ((port_index = fGraphManager->AllocatePort(fClientControl.fRefNum, buf,
                               JACK_DEFAULT_MIDI_TYPE,
-                              (JackPortFlags)port_flags,
+                              PlaybackDriverFlags,
                               fEngineControl->fBufferSize)) == NO_PORT) {
                 jack_error("driver: cannot register port for %s", buf);
                 return -1;
diff --git a/linux/freebob/JackFreebobDriver.cpp b/linux/freebob/JackFreebobDriver.cpp
index c5d5770a..348e4635 100644
--- a/linux/freebob/JackFreebobDriver.cpp
+++ b/linux/freebob/JackFreebobDriver.cpp
@@ -667,8 +667,7 @@ int JackFreebobDriver::Attach()
 {
     JackPort* port;
     int port_index;
-    unsigned long port_flags;
-
+  
     char buf[JACK_PORT_NAME_SIZE];
     char portname[JACK_PORT_NAME_SIZE];
 
@@ -717,8 +716,6 @@ int JackFreebobDriver::Attach()
     /* ports */
 
     // capture
-    port_flags = JackPortIsOutput | JackPortIsPhysical | JackPortIsTerminal;
-
     driver->capture_nchannels = freebob_streaming_get_nb_capture_streams(driver->dev);
     driver->capture_nchannels_audio = 0;
 
@@ -734,7 +731,7 @@ int JackFreebobDriver::Attach()
 
             if ((port_index = fGraphManager->AllocatePort(fClientControl.fRefNum, buf,
                               JACK_DEFAULT_AUDIO_TYPE,
-                              (JackPortFlags)port_flags,
+                              CaptureDriverFlags,
                               fEngineControl->fBufferSize)) == NO_PORT) {
                 jack_error("driver: cannot register port for %s", buf);
                 return -1;
@@ -748,8 +745,6 @@ int JackFreebobDriver::Attach()
     }
 
     // playback
-    port_flags = JackPortIsInput | JackPortIsPhysical | JackPortIsTerminal;
-
     driver->playback_nchannels = freebob_streaming_get_nb_playback_streams(driver->dev);
     driver->playback_nchannels_audio = 0;
 
@@ -764,7 +759,7 @@ int JackFreebobDriver::Attach()
             printMessage ("Registering playback port %s", buf);
             if ((port_index = fGraphManager->AllocatePort(fClientControl.fRefNum, buf,
                               JACK_DEFAULT_AUDIO_TYPE,
-                              (JackPortFlags)port_flags,
+                              PlaybackDriverFlags,
                               fEngineControl->fBufferSize)) == NO_PORT) {
                 jack_error("driver: cannot register port for %s", buf);
                 return -1;
diff --git a/macosx/coreaudio/JackCoreAudioDriver.cpp b/macosx/coreaudio/JackCoreAudioDriver.cpp
index 2143170f..2441375c 100644
--- a/macosx/coreaudio/JackCoreAudioDriver.cpp
+++ b/macosx/coreaudio/JackCoreAudioDriver.cpp
@@ -1560,8 +1560,7 @@ int JackCoreAudioDriver::Attach()
     char channel_name[64];
     char name[JACK_CLIENT_NAME_SIZE + JACK_PORT_NAME_SIZE];
     char alias[JACK_CLIENT_NAME_SIZE + JACK_PORT_NAME_SIZE];
-    unsigned long port_flags = JackPortIsOutput | JackPortIsPhysical | JackPortIsTerminal;
-
+ 
     jack_log("JackCoreAudioDriver::Attach fBufferSize %ld fSampleRate %ld", fEngineControl->fBufferSize, fEngineControl->fSampleRate);
 
     for (int i = 0; i < fCaptureChannels; i++) {
@@ -1580,7 +1579,7 @@ int JackCoreAudioDriver::Attach()
 
         snprintf(name, sizeof(name) - 1, "%s:capture_%d", fClientControl.fName, i + 1);
 
-        if ((port_index = fGraphManager->AllocatePort(fClientControl.fRefNum, name, JACK_DEFAULT_AUDIO_TYPE, (JackPortFlags)port_flags, fEngineControl->fBufferSize)) == NO_PORT) {
+        if ((port_index = fGraphManager->AllocatePort(fClientControl.fRefNum, name, JACK_DEFAULT_AUDIO_TYPE, CaptureDriverFlags, fEngineControl->fBufferSize)) == NO_PORT) {
             jack_error("Cannot register port for %s", name);
             return -1;
         }
@@ -1601,8 +1600,6 @@ int JackCoreAudioDriver::Attach()
         fCapturePortList[i] = port_index;
     }
 
-    port_flags = JackPortIsInput | JackPortIsPhysical | JackPortIsTerminal;
-
     for (int i = 0; i < fPlaybackChannels; i++) {
 
         err = AudioDeviceGetPropertyInfo(fDeviceID, i + 1, false, kAudioDevicePropertyChannelName, &size, &isWritable);
@@ -1619,7 +1616,7 @@ int JackCoreAudioDriver::Attach()
 
         snprintf(name, sizeof(name) - 1, "%s:playback_%d", fClientControl.fName, i + 1);
 
-        if ((port_index = fGraphManager->AllocatePort(fClientControl.fRefNum, name, JACK_DEFAULT_AUDIO_TYPE, (JackPortFlags)port_flags, fEngineControl->fBufferSize)) == NO_PORT) {
+        if ((port_index = fGraphManager->AllocatePort(fClientControl.fRefNum, name, JACK_DEFAULT_AUDIO_TYPE, PlaybackDriverFlags, fEngineControl->fBufferSize)) == NO_PORT) {
             jack_error("Cannot register port for %s", name);
             return -1;
         }
@@ -1644,7 +1641,7 @@ int JackCoreAudioDriver::Attach()
         if (fWithMonitorPorts) {
             jack_log("Create monitor port ");
             snprintf(name, sizeof(name) - 1, "%s:monitor_%u", fClientControl.fName, i + 1);
-            if ((port_index = fGraphManager->AllocatePort(fClientControl.fRefNum, name, JACK_DEFAULT_AUDIO_TYPE, JackPortIsOutput, fEngineControl->fBufferSize)) == NO_PORT) {
+            if ((port_index = fGraphManager->AllocatePort(fClientControl.fRefNum, name, JACK_DEFAULT_AUDIO_TYPE, MonitorDriverFlags, fEngineControl->fBufferSize)) == NO_PORT) {
                 jack_error("Cannot register monitor port for %s", name);
                 return -1;
             } else {
diff --git a/macosx/coremidi/JackCoreMidiDriver.cpp b/macosx/coremidi/JackCoreMidiDriver.cpp
index 08bd8c80..0f52e900 100644
--- a/macosx/coremidi/JackCoreMidiDriver.cpp
+++ b/macosx/coremidi/JackCoreMidiDriver.cpp
@@ -222,7 +222,6 @@ int JackCoreMidiDriver::Attach()
     char name[JACK_CLIENT_NAME_SIZE + JACK_PORT_NAME_SIZE];
     char endpoint_name[JACK_CLIENT_NAME_SIZE + JACK_PORT_NAME_SIZE];
     char alias[JACK_CLIENT_NAME_SIZE + JACK_PORT_NAME_SIZE];
-    unsigned long port_flags = JackPortIsOutput | JackPortIsPhysical | JackPortIsTerminal;
     int i;
 
     jack_log("JackCoreMidiDriver::Attach fBufferSize = %ld fSampleRate = %ld", fEngineControl->fBufferSize, fEngineControl->fSampleRate);
@@ -239,7 +238,7 @@ int JackCoreMidiDriver::Attach()
         }
         
         snprintf(name, sizeof(name) - 1, "%s:capture_%d", fClientControl.fName, i + 1);
-        if ((port_index = fGraphManager->AllocatePort(fClientControl.fRefNum, name, JACK_DEFAULT_MIDI_TYPE, (JackPortFlags)port_flags, fEngineControl->fBufferSize)) == NO_PORT) {
+        if ((port_index = fGraphManager->AllocatePort(fClientControl.fRefNum, name, JACK_DEFAULT_MIDI_TYPE, CaptureDriverFlags, fEngineControl->fBufferSize)) == NO_PORT) {
             jack_error("driver: cannot register port for %s", name);
             return -1;
         }
@@ -249,8 +248,6 @@ int JackCoreMidiDriver::Attach()
         jack_log("JackCoreMidiDriver::Attach fCapturePortList[i] port_index = %ld", port_index);
     }
 
-    port_flags = JackPortIsInput | JackPortIsPhysical | JackPortIsTerminal;
-
     for (i = 0; i < fPlaybackChannels; i++) {
         
         err = MIDIObjectGetStringProperty(fMidiSource[i], kMIDIPropertyName, &pname);
@@ -263,7 +260,7 @@ int JackCoreMidiDriver::Attach()
         }
         
         snprintf(name, sizeof(name) - 1, "%s:playback_%d", fClientControl.fName, i + 1);
-        if ((port_index = fGraphManager->AllocatePort(fClientControl.fRefNum, name, JACK_DEFAULT_MIDI_TYPE, (JackPortFlags)port_flags, fEngineControl->fBufferSize)) == NO_PORT) {
+        if ((port_index = fGraphManager->AllocatePort(fClientControl.fRefNum, name, JACK_DEFAULT_MIDI_TYPE, PlaybackDriverFlags, fEngineControl->fBufferSize)) == NO_PORT) {
             jack_error("driver: cannot register port for %s", name);
             return -1;
         }
diff --git a/tests/test.cpp b/tests/test.cpp
index 018b7499..b5d2467e 100644
--- a/tests/test.cpp
+++ b/tests/test.cpp
@@ -822,6 +822,8 @@ int main (int argc, char *argv[])
         printf("error : port_set_name function can't be tested...\n");
     }
 
+    port_callback_reg = 0;	// number of port registration received by the callback
+    
     /**
      * Activate the client
      *
@@ -840,6 +842,20 @@ int main (int argc, char *argv[])
 
     if (port_rename_clbk == 0)
         printf("!!! ERROR !!! Jack_Port_Rename_Callback was not called !!.\n");
+        
+        
+    /**
+     * Test if portregistration callback have been called.
+     *
+     */
+     
+    jack_sleep(1 * 1000); 
+
+    if (1 == port_callback_reg) {
+        Log("%i ports have been successfully created, and %i callback reg ports have been received... ok\n", 1, port_callback_reg);
+    } else {
+        printf("!!! ERROR !!! %i ports have been created, and %i callback reg ports have been received !\n", 1, port_callback_reg);
+    }
  
     /**
      * Test if init callback initThread have been called.
@@ -1095,11 +1111,14 @@ int main (int argc, char *argv[])
     }
 
     jack_sleep(1 * 1000); // To hope all port registration and reorder callback have been received...
+    
+    // Check port registration callback
     if (j == port_callback_reg) {
         Log("%i ports have been successfully created, and %i callback reg ports have been received... ok\n", j, port_callback_reg);
     } else {
-        printf("!!! ERROR !!! %i ports have been created, and %i callback reg ports have been received !\n", j, k);
+        printf("!!! ERROR !!! %i ports have been created, and %i callback reg ports have been received !\n", j, port_callback_reg);
     }
+    
     if (reorder == (2 * j)) {
         Log("%i graph reorder callback have been received... ok\n", reorder);
     } else {
@@ -1147,6 +1166,7 @@ int main (int argc, char *argv[])
      * Deregister all ports previously created.
      *
      */
+    port_callback_reg = 0; // to check registration callback
     Log("Deregistering all ports of the client...\n");
     inports = jack_get_ports(client1, NULL, NULL, 0);
     a = 0;
@@ -1160,6 +1180,13 @@ int main (int argc, char *argv[])
         }
         a++;
     }
+    
+    // Check port registration callback again
+    if (j == port_callback_reg) { 
+        Log("%i ports have been successfully created, and %i callback reg ports have been received... ok\n", j, port_callback_reg);
+    } else {
+        printf("!!! ERROR !!! %i ports have been created, and %i callback reg ports have been received !\n", j, port_callback_reg);
+    }
 
     free(inports); // free array of ports (as mentionned in the doc of jack_get_ports)
 
diff --git a/windows/winmme/JackWinMMEDriver.cpp b/windows/winmme/JackWinMMEDriver.cpp
index 65a7de65..b76a8299 100644
--- a/windows/winmme/JackWinMMEDriver.cpp
+++ b/windows/winmme/JackWinMMEDriver.cpp
@@ -289,7 +289,6 @@ int JackWinMMEDriver::Attach()
     jack_port_id_t port_index;
     char name[JACK_CLIENT_NAME_SIZE + JACK_PORT_NAME_SIZE];
     char alias[JACK_CLIENT_NAME_SIZE + JACK_PORT_NAME_SIZE];
-    unsigned long port_flags = JackPortIsOutput | JackPortIsPhysical | JackPortIsTerminal;
     MMRESULT res;
     int i;
 
@@ -305,7 +304,7 @@ int JackWinMMEDriver::Attach()
 		}
         snprintf(name, sizeof(name) - 1, "%s:capture_%d", fClientControl.fName, i + 1);
 
-        if ((port_index = fGraphManager->AllocatePort(fClientControl.fRefNum, name, JACK_DEFAULT_MIDI_TYPE, (JackPortFlags)port_flags, fEngineControl->fBufferSize)) == NO_PORT) {
+        if ((port_index = fGraphManager->AllocatePort(fClientControl.fRefNum, name, JACK_DEFAULT_MIDI_TYPE, CaptureDriverFlags, fEngineControl->fBufferSize)) == NO_PORT) {
             jack_error("driver: cannot register port for %s", name);
             return -1;
         }
@@ -315,8 +314,6 @@ int JackWinMMEDriver::Attach()
         jack_log("JackMidiDriver::Attach fCapturePortList[i] port_index = %ld", port_index);
     }
 
-    port_flags = JackPortIsInput | JackPortIsPhysical | JackPortIsTerminal;
-
     for (i = 0; i < fPlaybackChannels; i++) {
         MIDIOUTCAPS caps;
 		res = midiOutGetDevCaps(fMidiSource[i].fIndex, &caps, sizeof(caps));
@@ -327,7 +324,7 @@ int JackWinMMEDriver::Attach()
 		}
         snprintf(name, sizeof(name) - 1, "%s:playback_%d", fClientControl.fName, i + 1);
 
-        if ((port_index = fGraphManager->AllocatePort(fClientControl.fRefNum, name, JACK_DEFAULT_MIDI_TYPE, (JackPortFlags)port_flags, fEngineControl->fBufferSize)) == NO_PORT) {
+        if ((port_index = fGraphManager->AllocatePort(fClientControl.fRefNum, name, JACK_DEFAULT_MIDI_TYPE, PlaybackDriverFlags, fEngineControl->fBufferSize)) == NO_PORT) {
             jack_error("driver: cannot register port for %s", name);
             return -1;
         }