diff --git a/api/src/com/todoroo/andlib/data/AbstractModel.java b/api/src/com/todoroo/andlib/data/AbstractModel.java
index 6b770aea5..56bf3c5d1 100644
--- a/api/src/com/todoroo/andlib/data/AbstractModel.java
+++ b/api/src/com/todoroo/andlib/data/AbstractModel.java
@@ -11,6 +11,7 @@ import java.lang.reflect.Modifier;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.HashMap;
+import java.util.Map.Entry;
 import java.util.Set;
 
 import android.content.ContentValues;
@@ -21,6 +22,7 @@ import com.todoroo.andlib.data.Property.DoubleProperty;
 import com.todoroo.andlib.data.Property.IntegerProperty;
 import com.todoroo.andlib.data.Property.LongProperty;
 import com.todoroo.andlib.data.Property.PropertyVisitor;
+import com.todoroo.andlib.utility.AndroidUtilities;
 
 /**
  * <code>AbstractModel</code> represents a row in a database.
@@ -320,6 +322,20 @@ public abstract class AbstractModel implements Parcelable, Cloneable {
         setValues.putAll(other);
     }
 
+    /**
+     * Merges set values with those coming from another source,
+     * keeping the existing value if one already exists
+     */
+    public synchronized <TYPE> void mergeWithoutReplacement(ContentValues other) {
+        if (setValues == null)
+            setValues = new ContentValues();
+        for (Entry<String, Object> item : other.valueSet()) {
+            if (setValues.containsKey(item.getKey()))
+                continue;
+            AndroidUtilities.putInto(setValues, item.getKey(), item.getValue(), true);
+        }
+    }
+
     /**
      * Clear the key for the given property
      * @param property
diff --git a/astrid/src/com/todoroo/astrid/service/TaskService.java b/astrid/src/com/todoroo/astrid/service/TaskService.java
index 6a6389b28..bff5fb4f3 100644
--- a/astrid/src/com/todoroo/astrid/service/TaskService.java
+++ b/astrid/src/com/todoroo/astrid/service/TaskService.java
@@ -502,7 +502,7 @@ public class TaskService {
 
                 AndroidUtilities.putInto(forTask, key, value, true);
             }
-            task.mergeWith(forTask);
+            task.mergeWithoutReplacement(forTask);
         }
 
         if (task.getValue(Task.USER_ID) != Task.USER_ID_SELF)