diff --git a/core/java/android/net/MobileDataStateTracker.java b/core/java/android/net/MobileDataStateTracker.java
index 561294376335d..ff029206cf99d 100644
--- a/core/java/android/net/MobileDataStateTracker.java
+++ b/core/java/android/net/MobileDataStateTracker.java
@@ -184,8 +184,17 @@ public class MobileDataStateTracker implements NetworkStateTracker {
                 if (!TextUtils.equals(apnType, mApnType)) {
                     return;
                 }
-                mNetworkInfo.setSubtype(TelephonyManager.getDefault().getNetworkType(),
-                        TelephonyManager.getDefault().getNetworkTypeName());
+
+                int oldSubtype = mNetworkInfo.getSubtype();
+                int newSubType = TelephonyManager.getDefault().getNetworkType();
+                String subTypeName = TelephonyManager.getDefault().getNetworkTypeName();
+                mNetworkInfo.setSubtype(newSubType, subTypeName);
+                if (newSubType != oldSubtype && mNetworkInfo.isConnected()) {
+                    Message msg = mTarget.obtainMessage(EVENT_NETWORK_SUBTYPE_CHANGED,
+                                                        oldSubtype, 0, mNetworkInfo);
+                    msg.sendToTarget();
+                }
+
                 PhoneConstants.DataState state = Enum.valueOf(PhoneConstants.DataState.class,
                         intent.getStringExtra(PhoneConstants.STATE_KEY));
                 String reason = intent.getStringExtra(PhoneConstants.STATE_CHANGE_REASON_KEY);
diff --git a/core/java/android/net/NetworkStateTracker.java b/core/java/android/net/NetworkStateTracker.java
index 7df0193c8b1ea..0d6dcd6f34273 100644
--- a/core/java/android/net/NetworkStateTracker.java
+++ b/core/java/android/net/NetworkStateTracker.java
@@ -68,6 +68,12 @@ public interface NetworkStateTracker {
      */
     public static final int EVENT_RESTORE_DEFAULT_NETWORK = 6;
 
+    /**
+     * msg.what = EVENT_NETWORK_SUBTYPE_CHANGED
+     * msg.obj = NetworkInfo object
+     */
+    public static final int EVENT_NETWORK_SUBTYPE_CHANGED = 7;
+
     /**
      * -------------------------------------------------------------
      * Control Interface
diff --git a/services/java/com/android/server/ConnectivityService.java b/services/java/com/android/server/ConnectivityService.java
index 230f07bb5baf2..86ada4049a0c0 100644
--- a/services/java/com/android/server/ConnectivityService.java
+++ b/services/java/com/android/server/ConnectivityService.java
@@ -2490,6 +2490,11 @@ private NetworkStateTracker makeWimaxStateTracker() {
                     //       @see bug/4455071
                     handleConnectivityChange(info.getType(), false);
                     break;
+                case NetworkStateTracker.EVENT_NETWORK_SUBTYPE_CHANGED:
+                    info = (NetworkInfo) msg.obj;
+                    type = info.getType();
+                    updateNetworkSettings(mNetTrackers[type]);
+                    break;
                 case EVENT_CLEAR_NET_TRANSITION_WAKELOCK:
                     String causedBy = null;
                     synchronized (ConnectivityService.this) {