diff --git a/telephony/java/com/android/internal/telephony/BaseCommands.java b/telephony/java/com/android/internal/telephony/BaseCommands.java
index 3edca6669de0f..52f25f6b691c9 100644
--- a/telephony/java/com/android/internal/telephony/BaseCommands.java
+++ b/telephony/java/com/android/internal/telephony/BaseCommands.java
@@ -64,6 +64,7 @@ public abstract class BaseCommands implements CommandsInterface {
     protected RegistrantList mLineControlInfoRegistrants = new RegistrantList();
     protected RegistrantList mT53ClirInfoRegistrants = new RegistrantList();
     protected RegistrantList mT53AudCntrlInfoRegistrants = new RegistrantList();
+    protected RegistrantList mRingbackToneRegistrants = new RegistrantList();
 
     protected Registrant mSMSRegistrant;
     protected Registrant mNITZTimeRegistrant;
@@ -569,6 +570,15 @@ public abstract class BaseCommands implements CommandsInterface {
         mT53AudCntrlInfoRegistrants.remove(h);
     }
 
+    public void registerForRingbackTone(Handler h, int what, Object obj) {
+        Registrant r = new Registrant (h, what, obj);
+        mRingbackToneRegistrants.add(r);
+    }
+
+    public void unregisterForRingbackTone(Handler h) {
+        mRingbackToneRegistrants.remove(h);
+    }
+
     //***** Protected Methods
     /**
      * Store new RadioState and send notification based on the changes
diff --git a/telephony/java/com/android/internal/telephony/CommandsInterface.java b/telephony/java/com/android/internal/telephony/CommandsInterface.java
index 63bdc2c422c62..9d835561be89a 100644
--- a/telephony/java/com/android/internal/telephony/CommandsInterface.java
+++ b/telephony/java/com/android/internal/telephony/CommandsInterface.java
@@ -525,6 +525,17 @@ public interface CommandsInterface {
      void registerForCdmaOtaProvision(Handler h,int what, Object obj);
      void unregisterForCdmaOtaProvision(Handler h);
 
+     /**
+      * Registers the handler when out-band ringback tone is needed.<p>
+      *
+      *  Messages received from this:
+      *  Message.obj will be an AsyncResult
+      *  AsyncResult.userObj = obj
+      *  AsyncResult.result = boolean. <p>
+      */
+     void registerForRingbackTone(Handler h, int what, Object obj);
+     void unregisterForRingbackTone(Handler h);
+
     /**
      * Supply the ICC PIN to the ICC card
      *
diff --git a/telephony/java/com/android/internal/telephony/Phone.java b/telephony/java/com/android/internal/telephony/Phone.java
index f32837fae4b68..fffd128b79a73 100644
--- a/telephony/java/com/android/internal/telephony/Phone.java
+++ b/telephony/java/com/android/internal/telephony/Phone.java
@@ -379,6 +379,23 @@ public interface Phone {
 
     void unregisterForIncomingRing(Handler h);
 
+    /**
+     * Notifies when out-band ringback tone is needed.<p>
+     *
+     *  Messages received from this:
+     *  Message.obj will be an AsyncResult
+     *  AsyncResult.userObj = obj
+     *  AsyncResult.result = boolean, true to start play ringback tone
+     *                       and false to stop. <p>
+     */
+    void registerForRingbackTone(Handler h, int what, Object obj);
+
+    /**
+     * Unregisters for ringback tone notification.
+     */
+
+    void unregisterForRingbackTone(Handler h);
+
 
     /**
      * Notifies when a voice connection has disconnected, either due to local
diff --git a/telephony/java/com/android/internal/telephony/PhoneBase.java b/telephony/java/com/android/internal/telephony/PhoneBase.java
index e340f850e198d..1c62a82780b58 100644
--- a/telephony/java/com/android/internal/telephony/PhoneBase.java
+++ b/telephony/java/com/android/internal/telephony/PhoneBase.java
@@ -482,6 +482,16 @@ public abstract class PhoneBase extends Handler implements Phone {
         mServiceStateRegistrants.remove(h);
     }
 
+    // Inherited documentation suffices.
+    public void registerForRingbackTone(Handler h, int what, Object obj) {
+        mCM.registerForRingbackTone(h,what,obj);
+    }
+
+    // Inherited documentation suffices.
+    public void unregisterForRingbackTone(Handler h) {
+        mCM.unregisterForRingbackTone(h);
+    }
+
     /**
      * Subclasses of Phone probably want to replace this with a
      * version scoped to their packages
diff --git a/telephony/java/com/android/internal/telephony/PhoneProxy.java b/telephony/java/com/android/internal/telephony/PhoneProxy.java
index 711a48c8050f6..c4f663a20b89e 100644
--- a/telephony/java/com/android/internal/telephony/PhoneProxy.java
+++ b/telephony/java/com/android/internal/telephony/PhoneProxy.java
@@ -331,6 +331,14 @@ public class PhoneProxy extends Handler implements Phone {
         mActivePhone.unregisterForEcmTimerReset(h);
     }
 
+    public void registerForRingbackTone(Handler h, int what, Object obj) {
+        mActivePhone.registerForRingbackTone(h,what,obj);
+    }
+
+    public void unregisterForRingbackTone(Handler h) {
+        mActivePhone.unregisterForRingbackTone(h);
+    }
+
     public boolean getIccRecordsLoaded() {
         return mActivePhone.getIccRecordsLoaded();
     }
diff --git a/telephony/java/com/android/internal/telephony/RIL.java b/telephony/java/com/android/internal/telephony/RIL.java
index cd6340e140602..d1b446be81b79 100644
--- a/telephony/java/com/android/internal/telephony/RIL.java
+++ b/telephony/java/com/android/internal/telephony/RIL.java
@@ -2313,6 +2313,7 @@ public final class RIL extends BaseCommands implements CommandsInterface {
             case RIL_UNSOL_CDMA_OTA_PROVISION_STATUS: ret = responseInts(p); break;
             case RIL_UNSOL_CDMA_INFO_REC: ret = responseCdmaInformationRecord(p); break;
             case RIL_UNSOL_OEM_HOOK_RAW: ret = responseRaw(p); break;
+            case RIL_UNSOL_RINGBACK_TONE: ret = responseInts(p); break;
 
             default:
                 throw new RuntimeException("Unrecognized unsol response: " + response);
@@ -2597,6 +2598,14 @@ public final class RIL extends BaseCommands implements CommandsInterface {
                     mUnsolOemHookRawRegistrant.notifyRegistrant(new AsyncResult(null, ret, null));
                 }
                 break;
+
+            case RIL_UNSOL_RINGBACK_TONE:
+                if (RILJ_LOGD) unsljLogvRet(response, ret);
+                if (mRingbackToneRegistrants != null) {
+                    boolean playtone = (((int[])ret)[0] == 1);
+                    mRingbackToneRegistrants.notifyRegistrants(
+                                        new AsyncResult (null, playtone, null));
+                }
         }
     }
 
@@ -3209,6 +3218,7 @@ public final class RIL extends BaseCommands implements CommandsInterface {
             case RIL_UNSOL_CDMA_OTA_PROVISION_STATUS: return "UNSOL_CDMA_OTA_PROVISION_STATUS";
             case RIL_UNSOL_CDMA_INFO_REC: return "UNSOL_CDMA_INFO_REC";
             case RIL_UNSOL_OEM_HOOK_RAW: return "UNSOL_OEM_HOOK_RAW";
+            case RIL_UNSOL_RINGBACK_TONE: return "UNSOL_RINGBACK_TONG";
             default: return "<unknown reponse>";
         }
     }
diff --git a/telephony/java/com/android/internal/telephony/RILConstants.java b/telephony/java/com/android/internal/telephony/RILConstants.java
index 90a82f9082323..3e9d8ad5bb1ac 100644
--- a/telephony/java/com/android/internal/telephony/RILConstants.java
+++ b/telephony/java/com/android/internal/telephony/RILConstants.java
@@ -258,4 +258,5 @@ cat include/telephony/ril.h | \
     int RIL_UNSOL_CDMA_OTA_PROVISION_STATUS = 1026;
     int RIL_UNSOL_CDMA_INFO_REC = 1027;
     int RIL_UNSOL_OEM_HOOK_RAW = 1028;
+    int RIL_UNSOL_RINGBACK_TONE = 1029;
 }