diff --git a/api/src/com/todoroo/astrid/data/WaitingOnMe.java b/api/src/com/todoroo/astrid/data/WaitingOnMe.java
index 281adb454..81ca04ea0 100644
--- a/api/src/com/todoroo/astrid/data/WaitingOnMe.java
+++ b/api/src/com/todoroo/astrid/data/WaitingOnMe.java
@@ -5,6 +5,7 @@ import android.net.Uri;
 
 import com.todoroo.andlib.data.AbstractModel;
 import com.todoroo.andlib.data.Property;
+import com.todoroo.andlib.data.Property.IntegerProperty;
 import com.todoroo.andlib.data.Property.LongProperty;
 import com.todoroo.andlib.data.Property.StringProperty;
 import com.todoroo.andlib.data.Table;
@@ -50,6 +51,9 @@ public class WaitingOnMe extends RemoteModel {
     public static final LongProperty READ_AT = new LongProperty(
             TABLE, "read_at", Property.PROP_FLAG_DATE);
 
+    public static final IntegerProperty ACKNOWLEDGED = new IntegerProperty(
+            TABLE, "acknowledged", Property.PROP_FLAG_BOOLEAN);
+
     public static final LongProperty PUSHED_AT = new LongProperty(
             TABLE, PUSHED_AT_PROPERTY_NAME, Property.PROP_FLAG_DATE);
 
diff --git a/astrid/plugin-src/com/todoroo/astrid/actfm/sync/messages/NameMaps.java b/astrid/plugin-src/com/todoroo/astrid/actfm/sync/messages/NameMaps.java
index 6cd08b7f4..3816136c8 100644
--- a/astrid/plugin-src/com/todoroo/astrid/actfm/sync/messages/NameMaps.java
+++ b/astrid/plugin-src/com/todoroo/astrid/actfm/sync/messages/NameMaps.java
@@ -356,6 +356,7 @@ public class NameMaps {
         putWaitingOnMePropertyToServerName(WaitingOnMe.CREATED_AT,      "created_at",      false);
         putWaitingOnMePropertyToServerName(WaitingOnMe.DELETED_AT,      "deleted_at",      true);
         putWaitingOnMePropertyToServerName(WaitingOnMe.READ_AT,         "read_at",         true);
+        putWaitingOnMePropertyToServerName(WaitingOnMe.ACKNOWLEDGED,    "acknowledged",    true);
 
         // Reverse the mapping to construct the server to local map
         WAITING_ON_ME_PROPERTIES_SERVER_TO_LOCAL = AndroidUtilities.reverseMap(WAITING_ON_ME_PROPERTIES_LOCAL_TO_SERVER);