diff --git a/dom/bluetooth/bluedroid/BluetoothDaemonA2dpInterface.cpp b/dom/bluetooth/bluedroid/BluetoothDaemonA2dpInterface.cpp
index 7c958e7cc656..a212ba82c23c 100644
--- a/dom/bluetooth/bluedroid/BluetoothDaemonA2dpInterface.cpp
+++ b/dom/bluetooth/bluedroid/BluetoothDaemonA2dpInterface.cpp
@@ -14,6 +14,8 @@ BEGIN_BLUETOOTH_NAMESPACE
 // A2DP module
 //
 
+const int BluetoothDaemonA2dpModule::MAX_NUM_CLIENTS = 1;
+
 BluetoothA2dpNotificationHandler*
   BluetoothDaemonA2dpModule::sNotificationHandler;
 
@@ -342,7 +344,7 @@ BluetoothDaemonA2dpInterface::Init(
   }
 
   nsresult rv = mModule->RegisterModule(BluetoothDaemonA2dpModule::SERVICE_ID,
-                                        0x00, res);
+    0x00, BluetoothDaemonA2dpModule::MAX_NUM_CLIENTS, res);
   if (NS_FAILED(rv) && aRes) {
     DispatchError(aRes, STATUS_FAIL);
   }
diff --git a/dom/bluetooth/bluedroid/BluetoothDaemonA2dpInterface.h b/dom/bluetooth/bluedroid/BluetoothDaemonA2dpInterface.h
index 3a70b62714e9..bccf183cc57a 100644
--- a/dom/bluetooth/bluedroid/BluetoothDaemonA2dpInterface.h
+++ b/dom/bluetooth/bluedroid/BluetoothDaemonA2dpInterface.h
@@ -28,9 +28,12 @@ public:
     OPCODE_DISCONNECT = 0x02
   };
 
+  static const int MAX_NUM_CLIENTS;
+
   virtual nsresult Send(BluetoothDaemonPDU* aPDU, void* aUserData) = 0;
 
   virtual nsresult RegisterModule(uint8_t aId, uint8_t aMode,
+                                  uint32_t aMaxNumClients,
                                   BluetoothSetupResultHandler* aRes) = 0;
 
   virtual nsresult UnregisterModule(uint8_t aId,
diff --git a/dom/bluetooth/bluedroid/BluetoothDaemonHandsfreeInterface.cpp b/dom/bluetooth/bluedroid/BluetoothDaemonHandsfreeInterface.cpp
index bd956a6e96a7..a0dc78e6dc99 100644
--- a/dom/bluetooth/bluedroid/BluetoothDaemonHandsfreeInterface.cpp
+++ b/dom/bluetooth/bluedroid/BluetoothDaemonHandsfreeInterface.cpp
@@ -1318,7 +1318,8 @@ BluetoothDaemonHandsfreeInterface::Init(
   }
 
   nsresult rv = mModule->RegisterModule(
-    BluetoothDaemonHandsfreeModule::SERVICE_ID, MODE_NARROWBAND_SPEECH, res);
+    BluetoothDaemonHandsfreeModule::SERVICE_ID, MODE_NARROWBAND_SPEECH,
+    aMaxNumClients, res);
 
   if (NS_FAILED(rv) && aRes) {
     DispatchError(aRes, STATUS_FAIL);
diff --git a/dom/bluetooth/bluedroid/BluetoothDaemonHandsfreeInterface.h b/dom/bluetooth/bluedroid/BluetoothDaemonHandsfreeInterface.h
index 6b8d4b46b0ea..69c713a2f2e0 100644
--- a/dom/bluetooth/bluedroid/BluetoothDaemonHandsfreeInterface.h
+++ b/dom/bluetooth/bluedroid/BluetoothDaemonHandsfreeInterface.h
@@ -43,6 +43,7 @@ public:
   virtual nsresult Send(BluetoothDaemonPDU* aPDU, void* aUserData) = 0;
 
   virtual nsresult RegisterModule(uint8_t aId, uint8_t aMode,
+                                  uint32_t aMaxNumClients,
                                   BluetoothSetupResultHandler* aRes) = 0;
 
   virtual nsresult UnregisterModule(uint8_t aId,
diff --git a/dom/bluetooth/bluedroid/BluetoothDaemonHelpers.cpp b/dom/bluetooth/bluedroid/BluetoothDaemonHelpers.cpp
index 316721343627..2e2e9c9713c5 100644
--- a/dom/bluetooth/bluedroid/BluetoothDaemonHelpers.cpp
+++ b/dom/bluetooth/bluedroid/BluetoothDaemonHelpers.cpp
@@ -1259,6 +1259,12 @@ PackPDU(BluetoothSocketType aIn, BluetoothDaemonPDU& aPDU)
   return PackPDU(PackConversion<BluetoothSocketType, uint8_t>(aIn), aPDU);
 }
 
+nsresult
+PackPDU(BluetoothTransport aIn, BluetoothDaemonPDU& aPDU)
+{
+  return PackPDU(PackConversion<BluetoothTransport, uint8_t>(aIn), aPDU);
+}
+
 nsresult
 PackPDU(ControlPlayStatus aIn, BluetoothDaemonPDU& aPDU)
 {
diff --git a/dom/bluetooth/bluedroid/BluetoothDaemonHelpers.h b/dom/bluetooth/bluedroid/BluetoothDaemonHelpers.h
index c0d8cc58d643..2e4174e1497c 100644
--- a/dom/bluetooth/bluedroid/BluetoothDaemonHelpers.h
+++ b/dom/bluetooth/bluedroid/BluetoothDaemonHelpers.h
@@ -418,6 +418,9 @@ PackPDU(BluetoothSspPairingVariant aIn, BluetoothDaemonPDU& aPDU);
 nsresult
 PackPDU(BluetoothScanMode aIn, BluetoothDaemonPDU& aPDU);
 
+nsresult
+PackPDU(BluetoothTransport aIn, BluetoothDaemonPDU& aPDU);
+
 nsresult
 PackPDU(ControlPlayStatus aIn, BluetoothDaemonPDU& aPDU);
 
diff --git a/dom/bluetooth/bluedroid/BluetoothDaemonInterface.cpp b/dom/bluetooth/bluedroid/BluetoothDaemonInterface.cpp
index 4a8b24505c27..85812a31b983 100644
--- a/dom/bluetooth/bluedroid/BluetoothDaemonInterface.cpp
+++ b/dom/bluetooth/bluedroid/BluetoothDaemonInterface.cpp
@@ -31,13 +31,18 @@ public:
   //
 
   nsresult RegisterModuleCmd(uint8_t aId, uint8_t aMode,
+                             uint32_t aMaxNumClients,
                              BluetoothSetupResultHandler* aRes)
   {
     MOZ_ASSERT(NS_IsMainThread());
 
     nsAutoPtr<BluetoothDaemonPDU> pdu(new BluetoothDaemonPDU(0x00, 0x01, 0));
 
+#if ANDROID_VERSION >= 21
+    nsresult rv = PackPDU(aId, aMode, aMaxNumClients, *pdu);
+#else
     nsresult rv = PackPDU(aId, aMode, *pdu);
+#endif
     if (NS_FAILED(rv)) {
       return rv;
     }
@@ -188,6 +193,9 @@ static BluetoothNotificationHandler* sNotificationHandler;
 class BluetoothDaemonCoreModule
 {
 public:
+
+  static const int MAX_NUM_CLIENTS;
+
   virtual nsresult Send(BluetoothDaemonPDU* aPDU, void* aUserData) = 0;
 
   nsresult EnableCmd(BluetoothResultHandler* aRes)
@@ -413,8 +421,13 @@ public:
 
     nsAutoPtr<BluetoothDaemonPDU> pdu(new BluetoothDaemonPDU(0x01, 0x0d, 0));
 
+#if ANDROID_VERSION >= 21
+    nsresult rv = PackPDU(
+      PackConversion<nsAString, BluetoothAddress>(aBdAddr), aTransport, *pdu);
+#else
     nsresult rv = PackPDU(
       PackConversion<nsAString, BluetoothAddress>(aBdAddr), *pdu);
+#endif
     if (NS_FAILED(rv)) {
       return rv;
     }
@@ -1354,6 +1367,8 @@ private:
 
 };
 
+const int BluetoothDaemonCoreModule::MAX_NUM_CLIENTS = 1;
+
 //
 // Protocol handling
 //
@@ -1418,7 +1433,7 @@ class BluetoothDaemonProtocol MOZ_FINAL
 public:
   BluetoothDaemonProtocol(BluetoothDaemonConnection* aConnection);
 
-  nsresult RegisterModule(uint8_t aId, uint8_t aMode,
+  nsresult RegisterModule(uint8_t aId, uint8_t aMode, uint32_t aMaxNumClients,
                           BluetoothSetupResultHandler* aRes) MOZ_OVERRIDE;
 
   nsresult UnregisterModule(uint8_t aId,
@@ -1465,9 +1480,11 @@ BluetoothDaemonProtocol::BluetoothDaemonProtocol(
 
 nsresult
 BluetoothDaemonProtocol::RegisterModule(uint8_t aId, uint8_t aMode,
+                                        uint32_t aMaxNumClients,
                                         BluetoothSetupResultHandler* aRes)
 {
-  return BluetoothDaemonSetupModule::RegisterModuleCmd(aId, aMode, aRes);
+  return BluetoothDaemonSetupModule::RegisterModuleCmd(aId, aMode,
+                                                       aMaxNumClients, aRes);
 }
 
 nsresult
@@ -1747,7 +1764,8 @@ public:
     if (!mRegisteredSocketModule) {
       mRegisteredSocketModule = true;
       // Init, step 4: Register Socket module
-      mInterface->mProtocol->RegisterModuleCmd(0x02, 0x00, this);
+      mInterface->mProtocol->RegisterModuleCmd(0x02, 0x00,
+        BluetoothDaemonSocketModule::MAX_NUM_CLIENTS, this);
     } else if (mRes) {
       // Init, step 5: Signal success to caller
       mRes->Init();
@@ -1786,7 +1804,8 @@ BluetoothDaemonInterface::OnConnectSuccess(enum Channel aChannel)
 
         // Init, step 3: Register Core module
         nsresult rv = mProtocol->RegisterModuleCmd(
-          0x01, 0x00, new InitResultHandler(this, res));
+          0x01, 0x00, BluetoothDaemonCoreModule::MAX_NUM_CLIENTS,
+          new InitResultHandler(this, res));
         if (NS_FAILED(rv) && res) {
           DispatchError(res, STATUS_FAIL);
         }
diff --git a/dom/bluetooth/bluedroid/BluetoothDaemonSocketInterface.cpp b/dom/bluetooth/bluedroid/BluetoothDaemonSocketInterface.cpp
index 7acfae65f502..7022d19a3f15 100644
--- a/dom/bluetooth/bluedroid/BluetoothDaemonSocketInterface.cpp
+++ b/dom/bluetooth/bluedroid/BluetoothDaemonSocketInterface.cpp
@@ -15,6 +15,8 @@ BEGIN_BLUETOOTH_NAMESPACE
 // Socket module
 //
 
+const int BluetoothDaemonSocketModule::MAX_NUM_CLIENTS = 1;
+
 // Commands
 //
 
diff --git a/dom/bluetooth/bluedroid/BluetoothDaemonSocketInterface.h b/dom/bluetooth/bluedroid/BluetoothDaemonSocketInterface.h
index 08243fa1d667..cda13c52774e 100644
--- a/dom/bluetooth/bluedroid/BluetoothDaemonSocketInterface.h
+++ b/dom/bluetooth/bluedroid/BluetoothDaemonSocketInterface.h
@@ -20,6 +20,8 @@ class BlutoothDaemonInterface;
 class BluetoothDaemonSocketModule
 {
 public:
+  static const int MAX_NUM_CLIENTS;
+
   virtual nsresult Send(BluetoothDaemonPDU* aPDU, void* aUserData) = 0;
 
   // Commands