diff --git a/lib/observer.js b/lib/observer.js
index dfc8317..6b44d16 100644
--- a/lib/observer.js
+++ b/lib/observer.js
@@ -82,7 +82,14 @@ angular.module('OmniBinder')
      *              the removed and added objects.
     */
     this.observeObjectInCollection = function (context, collection, object, callback) {
-      function onObjectObserved (changes) {
+      function onObjectObserved(added, removed, changed, getOldValueFn) {
+        var changes = [{
+          added:   added,
+          removed: removed,
+          changed: changed,
+          index:   getOldValueFn(context.key)
+        }];
+
         /*
           An empty array to hold splice objects that will be created.
           Splices will look like splices generated natively from Array.observe().
@@ -109,8 +116,7 @@ angular.module('OmniBinder')
         }
       }
 
-      this.observers[object] = onObjectObserved;
-      Object.observe(object, onObjectObserved);
+      this.observers[object] = new ObjectObserver(object, onObjectObserved);
     };
 
     /*
@@ -181,7 +187,7 @@ angular.module('OmniBinder')
         if (change.removed.length) {
           //Unobserve each item
           angular.forEach(change.removed, function unObserve (obj) {
-            Object.unobserve(obj, self.observers[obj]);
+            self.observers[obj].close();
           });
         }
       }