diff --git a/AndroidManifest.xml b/AndroidManifest.xml
index febb6e4..f1d293f 100644
--- a/AndroidManifest.xml
+++ b/AndroidManifest.xml
@@ -458,6 +458,20 @@
             </intent-filter>
         </receiver>
 
+        <!-- Activation service that trigger OTASP sim provisioning -->
+        <service android:name=".otasp.OtaspActivationService" android:launchMode="singleInstance"
+                 androidprv:systemUserOnly="true">
+            <intent-filter>
+                <action android:name="android.service.simActivation.SimActivationService" />
+            </intent-filter>
+        </service>
+
+        <receiver android:name=".otasp.OtaspSimStateReceiver" android:exported ="false">
+            <intent-filter>
+                <action android:name="android.telephony.action.CARRIER_CONFIG_CHANGED" />
+            </intent-filter>
+        </receiver>
+
         <!-- "Accessibility" settings UI. Referenced by Dialer application. -->
         <activity android:name="com.android.phone.settings.AccessibilitySettingsActivity"
                 android:label="@string/accessibility_settings_activity_title"
diff --git a/res/values-mcc208-mnc09-fr/strings.xml b/res/values-mcc208-mnc09-fr/strings.xml
new file mode 100644
index 0000000..ac5ef59
--- /dev/null
+++ b/res/values-mcc208-mnc09-fr/strings.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<resources xmlns:android="http://schemas.android.com/apk/res/android" xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+    <string name="enhanced_4g_lte_mode_summary">Utiliser la fonction Voix 4G (HD) lorsqu\'elle est disponible</string>
+    <string name="enhanced_4g_lte_mode_title">Activer Voix 4G (HD)</string>
+</resources>
diff --git a/res/values-mcc208-mnc10-fr/strings.xml b/res/values-mcc208-mnc10-fr/strings.xml
new file mode 100644
index 0000000..ac5ef59
--- /dev/null
+++ b/res/values-mcc208-mnc10-fr/strings.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<resources xmlns:android="http://schemas.android.com/apk/res/android" xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+    <string name="enhanced_4g_lte_mode_summary">Utiliser la fonction Voix 4G (HD) lorsqu\'elle est disponible</string>
+    <string name="enhanced_4g_lte_mode_title">Activer Voix 4G (HD)</string>
+</resources>
diff --git a/res/values/strings.xml b/res/values/strings.xml
index f89ed64..ec7d761 100644
--- a/res/values/strings.xml
+++ b/res/values/strings.xml
@@ -999,8 +999,6 @@
     <string name="incall_error_call_failed">Call failed.</string>
     <!-- In-call screen: call failure message displayed in an error dialog -->
     <string name="incall_error_cannot_add_call">Call cannot be added at this time.</string>
-    <!-- In-call screen: status message displayed in a dialog when starting an MMI -->
-    <string name="incall_status_dialed_mmi">Starting MMI sequence\u2026</string>
     <!-- In-call screen: message displayed in an error dialog -->
     <string name="incall_error_supp_service_unknown">Service not supported</string>
     <!-- In-call screen: message displayed in an error dialog -->
@@ -1368,6 +1366,12 @@
         Unable to connect, please insert a valid SIM card.
     </string>
 
+    <!-- Call failure reason displayed when an in-progress WIFI call fails due to a loss of WIFI
+         connectivity, or the WIFI signal has degraded to the point the call cannot continue. -->
+    <string name="callFailed_wifi_lost">
+        Wi-Fi connection lost.  Call ended.
+    </string>
+
     <!-- The title for the change voicemail PIN activity -->
     <string name="change_pin_title">Change Voicemail PIN</string>
     <!-- The label for the continue button in change voicemail PIN activity -->
diff --git a/src/com/android/phone/MMIDialogActivity.java b/src/com/android/phone/MMIDialogActivity.java
index 10ec6a3..5ac6b85 100644
--- a/src/com/android/phone/MMIDialogActivity.java
+++ b/src/com/android/phone/MMIDialogActivity.java
@@ -63,9 +63,6 @@
                 }
         };
         mCM.registerForMmiComplete(mHandler, PhoneGlobals.MMI_COMPLETE, null);
-        if (mCM.getState() == PhoneConstants.State.OFFHOOK) {
-            Toast.makeText(this, R.string.incall_status_dialed_mmi, Toast.LENGTH_SHORT).show();
-        }
         showMMIDialog();
     }
 
diff --git a/src/com/android/phone/PhoneUtils.java b/src/com/android/phone/PhoneUtils.java
index 9f70349..6fdff14 100644
--- a/src/com/android/phone/PhoneUtils.java
+++ b/src/com/android/phone/PhoneUtils.java
@@ -86,9 +86,9 @@
     static final String ADD_CALL_MODE_KEY = "add_call_mode";
 
     // Return codes from placeCall()
-    static final int CALL_STATUS_DIALED = 0;  // The number was successfully dialed
-    static final int CALL_STATUS_DIALED_MMI = 1;  // The specified number was an MMI code
-    static final int CALL_STATUS_FAILED = 2;  // The call failed
+    public static final int CALL_STATUS_DIALED = 0;  // The number was successfully dialed
+    public static final int CALL_STATUS_DIALED_MMI = 1;  // The specified number was an MMI code
+    public static final int CALL_STATUS_FAILED = 2;  // The call failed
 
     // State of the Phone's audio modes
     // Each state can move to the other states, but within the state only certain
diff --git a/src/com/android/phone/otasp/OtaspActivationService.java b/src/com/android/phone/otasp/OtaspActivationService.java
new file mode 100644
index 0000000..504315f
--- /dev/null
+++ b/src/com/android/phone/otasp/OtaspActivationService.java
@@ -0,0 +1,213 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.android.phone.otasp;
+
+import android.app.Service;
+import android.content.Intent;
+import android.os.AsyncResult;
+import android.os.Handler;
+import android.os.IBinder;
+import android.os.Message;
+import android.telephony.ServiceState;
+
+import com.android.internal.telephony.Phone;
+import com.android.internal.telephony.PhoneConstants;
+import com.android.phone.PhoneGlobals;
+import com.android.phone.PhoneUtils;
+
+import static com.android.phone.PhoneGlobals.getPhone;
+
+/**
+ * otasp activation service handles all logic related with OTASP call.
+ * OTASP is a CDMA-specific feature: OTA or OTASP == Over The Air service provisioning
+ * In practice, in a normal successful OTASP call, events come in as follows:
+ * - SPL_UNLOCKED within a couple of seconds after the call starts
+ * - PRL_DOWNLOADED and MDN_DOWNLOADED and COMMITTED within a span of 2 seconds
+ * - poll cdma subscription from RIL after COMMITTED
+ * - SIM reloading with provisioned MDN and MIN
+ */
+public class OtaspActivationService extends Service {
+    private static final String TAG = OtaspActivationService.class.getSimpleName();
+    private static final boolean DBG = true;
+    /* non-interactive otasp number */
+    private static final String OTASP_NUMBER = "*22899";
+
+    /**
+     * Otasp call follows with SIM reloading which might triggers a retry loop on activation
+     * failure. A max retry limit could help prevent retry loop.
+     */
+    private static final int OTASP_CALL_RETRIES_MAX = 3;
+    private static final int OTASP_CALL_RETRY_PERIOD_IN_MS = 3000;
+    private static int sOtaspCallRetries = 0;
+
+    /* events */
+    private static final int EVENT_CALL_STATE_CHANGED                     = 0;
+    private static final int EVENT_CDMA_OTASP_CALL_RETRY                  = 1;
+    private static final int EVENT_CDMA_PROVISION_STATUS_UPDATE           = 2;
+    private static final int EVENT_SERVICE_STATE_CHANGED                  = 3;
+    private static final int EVENT_START_OTASP_CALL                       = 4;
+
+    /* use iccid to detect hot sim swap */
+    private static String sIccId = null;
+
+    private Phone mPhone;
+    /* committed flag indicates Otasp call succeed */
+    private boolean mIsOtaspCallCommitted = false;
+
+    @Override
+    public void onCreate() {
+        logd("otasp service onCreate");
+        mPhone = PhoneGlobals.getPhone();
+        if ((sIccId == null) || !sIccId.equals(mPhone.getIccSerialNumber())) {
+            // reset to allow activation retry on new sim
+            sIccId = mPhone.getIccSerialNumber();
+            sOtaspCallRetries = 0;
+        }
+        sOtaspCallRetries++;
+        logd("OTASP call tried " + sOtaspCallRetries + " times");
+        if (sOtaspCallRetries > OTASP_CALL_RETRIES_MAX) {
+            logd("OTASP call exceeds max retries => activation failed");
+            //TODO updateActivationState(DEACTIVATED)
+            onComplete();
+            return;
+        }
+        mHandler.sendEmptyMessage(EVENT_START_OTASP_CALL);
+    }
+
+    @Override
+    public int onStartCommand(Intent intent, int flags, int startId) {
+        return START_REDELIVER_INTENT;
+    }
+
+    @Override
+    public IBinder onBind(Intent intent) {
+        return null;
+    }
+
+    private Handler mHandler = new Handler() {
+        @Override
+        public void handleMessage(Message msg) {
+            switch (msg.what) {
+                case EVENT_SERVICE_STATE_CHANGED:
+                    logd("EVENT_SERVICE_STATE_CHANGED");
+                    onStartOtaspCall();
+                    break;
+                case EVENT_START_OTASP_CALL:
+                    logd("EVENT_START_OTASP_CALL");
+                    onStartOtaspCall();
+                    break;
+                case EVENT_CALL_STATE_CHANGED:
+                    logd("OTASP_CALL_STATE_CHANGED");
+                    onOtaspCallStateChanged();
+                    break;
+                case EVENT_CDMA_PROVISION_STATUS_UPDATE:
+                    logd("OTASP_ACTIVATION_STATUS_UPDATE_EVENT");
+                    onCdmaProvisionStatusUpdate((AsyncResult) msg.obj);
+                    break;
+                case EVENT_CDMA_OTASP_CALL_RETRY:
+                    logd("EVENT_CDMA_OTASP_CALL_RETRY");
+                    onStartOtaspCall();
+                    break;
+                default:
+                    loge("invalid msg: " + msg.what + " not handled.");
+            }
+        }
+    };
+
+    /**
+     * Starts the OTASP call without any UI.
+     * platform only support background non-interactive otasp call, but users could still dial
+     * interactive OTASP number through dialer if carrier allows (some carrier will
+     * explicitly block any outgoing *288XX number).
+     */
+    private void onStartOtaspCall() {
+        unregisterAll();
+        if (mPhone.getServiceState().getState() != ServiceState.STATE_IN_SERVICE) {
+            loge("OTASP call failure, wait for network available.");
+            mPhone.registerForServiceStateChanged(mHandler, EVENT_SERVICE_STATE_CHANGED, null);
+            return;
+        }
+        // otasp call follows with CDMA OTA PROVISION STATUS update which signals activation result
+        mPhone.registerForCdmaOtaStatusChange(mHandler, EVENT_CDMA_PROVISION_STATUS_UPDATE, null);
+        mPhone.registerForPreciseCallStateChanged(mHandler, EVENT_CALL_STATE_CHANGED, null);
+        logd("startNonInteractiveOtasp: placing call to '" + OTASP_NUMBER + "'...");
+        int callStatus = PhoneUtils.placeCall(this,
+                getPhone(),
+                OTASP_NUMBER,
+                null,   // contactRef
+                false); // isEmergencyCall
+        if (callStatus == PhoneUtils.CALL_STATUS_DIALED) {
+            if (DBG) logd("  ==> success return from placeCall(): callStatus = " + callStatus);
+        } else {
+            loge(" ==> failure return from placeCall(): callStatus = " + callStatus);
+            mHandler.sendEmptyMessageDelayed(EVENT_CDMA_OTASP_CALL_RETRY,
+                    OTASP_CALL_RETRY_PERIOD_IN_MS);
+        }
+    }
+
+    /**
+     * register for cdma ota provision status
+     * see RIL_CDMA_OTA_ProvisionStatus in include/telephony/ril.h
+     */
+    private void onCdmaProvisionStatusUpdate(AsyncResult r) {
+        int[] otaStatus = (int[]) r.result;
+        logd("onCdmaProvisionStatusUpdate: " + otaStatus[0]);
+        if (Phone.CDMA_OTA_PROVISION_STATUS_COMMITTED == otaStatus[0]) {
+            mIsOtaspCallCommitted = true;
+        }
+    }
+
+    /**
+     * update activation state upon call disconnected.
+     * check the mIsOtaspCallCommitted bit, and if that's true it means that activation
+     * was successful.
+     */
+    private void onOtaspCallStateChanged() {
+        logd("onOtaspCallStateChanged: " + mPhone.getState());
+        if (mPhone.getState().equals(PhoneConstants.State.IDLE)) {
+            if (mIsOtaspCallCommitted) {
+                logd("Otasp activation succeed");
+                //TODO updateActivationState(ACTIVATED)
+            } else {
+                logd("Otasp activation failed");
+                //TODO updateActivationState(DEACTIVATED)
+            }
+            onComplete();
+        }
+    }
+
+    private void onComplete() {
+        logd("otasp service onComplete");
+        unregisterAll();
+        stopSelf();
+    }
+
+    private void unregisterAll() {
+        mPhone.unregisterForCdmaOtaStatusChange(mHandler);
+        mPhone.unregisterForSubscriptionInfoReady(mHandler);
+        mPhone.unregisterForServiceStateChanged(mHandler);
+        mPhone.unregisterForPreciseCallStateChanged(mHandler);
+        mHandler.removeCallbacksAndMessages(null);
+    }
+
+    private static void logd(String s) {
+        android.util.Log.d(TAG, s);
+    }
+
+    private static void loge(String s) {
+        android.util.Log.e(TAG, s);
+    }
+}
diff --git a/src/com/android/phone/otasp/OtaspSimStateReceiver.java b/src/com/android/phone/otasp/OtaspSimStateReceiver.java
new file mode 100644
index 0000000..ef34e20
--- /dev/null
+++ b/src/com/android/phone/otasp/OtaspSimStateReceiver.java
@@ -0,0 +1,85 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.android.phone.otasp;
+
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.os.PersistableBundle;
+import android.telephony.CarrierConfigManager;
+import android.telephony.PhoneStateListener;
+import android.telephony.TelephonyManager;
+import android.util.Log;
+import com.android.internal.telephony.Phone;
+import com.android.internal.telephony.ServiceStateTracker;
+import com.android.phone.PhoneGlobals;
+
+public class OtaspSimStateReceiver extends BroadcastReceiver {
+    private static final String TAG = OtaspSimStateReceiver.class.getSimpleName();
+    private static final boolean DBG = true;
+    private Context mContext;
+
+    private PhoneStateListener mPhoneStateListener = new PhoneStateListener(){
+        @Override
+        public void onOtaspChanged(int otaspMode) {
+            logd("onOtaspChanged: otaspMode=" + otaspMode);
+            if (otaspMode == ServiceStateTracker.OTASP_NEEDED && isCarrierSupported()
+                    && PhoneGlobals.getPhone().getIccRecordsLoaded()) {
+                logd("otasp activation required, start otaspActivationService");
+                mContext.startService(new Intent(mContext, OtaspActivationService.class));
+            }
+        }
+    };
+
+    /**
+     * check if OTA service provisioning activation is supported by the current carrier
+     * @return true if otasp activation is needed, false otherwise
+     */
+    private static boolean isCarrierSupported() {
+        final Phone phone = PhoneGlobals.getPhone();
+        final Context context = phone.getContext();
+        if (context != null) {
+            PersistableBundle b = null;
+            final CarrierConfigManager configManager = (CarrierConfigManager) context
+                    .getSystemService(Context.CARRIER_CONFIG_SERVICE);
+            if (configManager != null) {
+                b = configManager.getConfig();
+            }
+            if (b != null && b.getBoolean(
+                    CarrierConfigManager.KEY_USE_OTASP_FOR_PROVISIONING_BOOL)) {
+                return true;
+            }
+        }
+        logd("otasp activation not needed: no supported carrier");
+        return false;
+    }
+
+    @Override
+    public void onReceive(Context context, Intent intent) {
+        mContext = context;
+        if(CarrierConfigManager.ACTION_CARRIER_CONFIG_CHANGED.equals(intent.getAction())) {
+            if (DBG) logd("Received intent: " + intent.getAction());
+            final TelephonyManager telephonyManager = (TelephonyManager) context
+                    .getSystemService(Context.TELEPHONY_SERVICE);
+            telephonyManager.listen(mPhoneStateListener, PhoneStateListener.LISTEN_OTASP_CHANGED);
+        }
+    }
+
+    private static void logd(String s) {
+        Log.d(TAG, s);
+    }
+}
+
diff --git a/src/com/android/services/telephony/CdmaConnection.java b/src/com/android/services/telephony/CdmaConnection.java
index 8020996..29ccc6c 100644
--- a/src/com/android/services/telephony/CdmaConnection.java
+++ b/src/com/android/services/telephony/CdmaConnection.java
@@ -184,7 +184,7 @@
     }
 
     @Override
-    public void performConference(TelephonyConnection otherConnection) {
+    public void performConference(android.telecom.Connection otherConnection) {
         if (isImsConnection()) {
             super.performConference(otherConnection);
         } else {
diff --git a/src/com/android/services/telephony/DisconnectCauseUtil.java b/src/com/android/services/telephony/DisconnectCauseUtil.java
index 534f510..c356899 100644
--- a/src/com/android/services/telephony/DisconnectCauseUtil.java
+++ b/src/com/android/services/telephony/DisconnectCauseUtil.java
@@ -130,6 +130,7 @@
             case android.telephony.DisconnectCause.DATA_LIMIT_REACHED:
             case android.telephony.DisconnectCause.DIALED_ON_WRONG_SLOT:
             case android.telephony.DisconnectCause.IMEI_NOT_ACCEPTED:
+            case android.telephony.DisconnectCause.WIFI_LOST:
                 return DisconnectCause.ERROR;
 
             case android.telephony.DisconnectCause.DIALED_MMI:
@@ -386,6 +387,10 @@
                 resourceId = R.string.callFailed_imei_not_accepted;
                 break;
 
+            case android.telephony.DisconnectCause.WIFI_LOST:
+                resourceId = R.string.callFailed_wifi_lost;
+                break;
+
             default:
                 break;
         }
diff --git a/src/com/android/services/telephony/ImsConference.java b/src/com/android/services/telephony/ImsConference.java
index e924b0d..6c4fadc 100644
--- a/src/com/android/services/telephony/ImsConference.java
+++ b/src/com/android/services/telephony/ImsConference.java
@@ -443,7 +443,7 @@
     @Override
     public void onMerge(android.telecom.Connection connection) {
         try {
-            Phone phone = ((TelephonyConnection) connection).getPhone();
+            Phone phone = mConferenceHost.getPhone();
             if (phone != null) {
                 phone.conference();
             }
diff --git a/src/com/android/services/telephony/ImsConferenceController.java b/src/com/android/services/telephony/ImsConferenceController.java
index d151693..4df6444 100644
--- a/src/com/android/services/telephony/ImsConferenceController.java
+++ b/src/com/android/services/telephony/ImsConferenceController.java
@@ -187,6 +187,7 @@
         Log.v(this, "recalculateConferenceable : %d", mTelephonyConnections.size());
         HashSet<Conferenceable> conferenceableSet = new HashSet<>(mTelephonyConnections.size() +
                 mImsConferences.size());
+        HashSet<Conferenceable> conferenceParticipantsSet = new HashSet<>();
 
         // Loop through and collect all calls which are active or holding
         for (TelephonyConnection connection : mTelephonyConnections) {
@@ -240,6 +241,7 @@
                 case Connection.STATE_ACTIVE:
                     //fall through
                 case Connection.STATE_HOLDING:
+                    conferenceParticipantsSet.addAll(conference.getConnections());
                     conferenceableSet.add(conference);
                     continue;
                 default:
@@ -256,6 +258,16 @@
                         .stream()
                         .filter(conferenceable -> c != conferenceable)
                         .collect(Collectors.toList());
+                // TODO: Remove this once RemoteConnection#setConferenceableConnections is fixed.
+                // Add all conference participant connections as conferenceable with a standalone
+                // Connection.  We need to do this to ensure that RemoteConnections work properly.
+                // At the current time, a RemoteConnection will not be conferenceable with a
+                // Conference, so we need to add its children to ensure the user can merge the call
+                // into the conference.
+                // We should add support for RemoteConnection#setConferenceables, which accepts a
+                // list of remote conferences and connections in the future.
+                conferenceables.addAll(conferenceParticipantsSet);
+
                 ((Connection) c).setConferenceables(conferenceables);
             } else if (c instanceof Conference) {
                 // Remove all conferences from the set, since we can not conference a conference
diff --git a/src/com/android/services/telephony/TelephonyConnection.java b/src/com/android/services/telephony/TelephonyConnection.java
index 62343b9..5ae1a26 100644
--- a/src/com/android/services/telephony/TelephonyConnection.java
+++ b/src/com/android/services/telephony/TelephonyConnection.java
@@ -683,7 +683,7 @@
         }
     }
 
-    public void performConference(TelephonyConnection otherConnection) {
+    public void performConference(Connection otherConnection) {
         Log.d(this, "performConference - %s", this);
         if (getPhone() != null) {
             try {
diff --git a/src/com/android/services/telephony/TelephonyConnectionService.java b/src/com/android/services/telephony/TelephonyConnectionService.java
index 77a7cfb..279f087 100644
--- a/src/com/android/services/telephony/TelephonyConnectionService.java
+++ b/src/com/android/services/telephony/TelephonyConnectionService.java
@@ -617,14 +617,35 @@
         }
     }
 
+    /**
+     * Conferences two connections.
+     *
+     * Note: The {@link android.telecom.RemoteConnection#setConferenceableConnections(List)} API has
+     * a limitation in that it can only specify conferenceables which are instances of
+     * {@link android.telecom.RemoteConnection}.  In the case of an {@link ImsConference}, the
+     * regular {@link Connection#setConferenceables(List)} API properly handles being able to merge
+     * a {@link Conference} and a {@link Connection}.  As a result when, merging a
+     * {@link android.telecom.RemoteConnection} into a {@link android.telecom.RemoteConference}
+     * require merging a {@link ConferenceParticipantConnection} which is a child of the
+     * {@link Conference} with a {@link TelephonyConnection}.  The
+     * {@link ConferenceParticipantConnection} class does not have the capability to initiate a
+     * conference merge, so we need to call
+     * {@link TelephonyConnection#performConference(Connection)} on either {@code connection1} or
+     * {@code connection2}, one of which is an instance of {@link TelephonyConnection}.
+     *
+     * @param connection1 A connection to merge into a conference call.
+     * @param connection2 A connection to merge into a conference call.
+     */
     @Override
     public void onConference(Connection connection1, Connection connection2) {
-        if (connection1 instanceof TelephonyConnection &&
-                connection2 instanceof TelephonyConnection) {
-            ((TelephonyConnection) connection1).performConference(
-                (TelephonyConnection) connection2);
+        if (connection1 instanceof TelephonyConnection) {
+            ((TelephonyConnection) connection1).performConference(connection2);
+        } else if (connection2 instanceof TelephonyConnection) {
+            ((TelephonyConnection) connection2).performConference(connection1);
+        } else {
+            Log.w(this, "onConference - cannot merge connections " +
+                    "Connection1: %s, Connection2: %2", connection1, connection2);
         }
-
     }
 
     private boolean isRadioOn() {