diff --git a/lib/abstract-class.js b/lib/abstract-class.js
index 8934fc26..f4cd0be4 100644
--- a/lib/abstract-class.js
+++ b/lib/abstract-class.js
@@ -595,7 +595,7 @@ AbstractClass.prototype.fromObject = function (obj) {
  * @return Boolean
  */
 AbstractClass.prototype.propertyChanged = function propertyChanged(attr) {
-    return this['_' + attr] !== this[attr + '_was'];
+    return this.hasOwnProperty(attr + '_was') && this['_' + attr] !== this[attr + '_was'];
 };
 
 /**
diff --git a/test/common_test.js b/test/common_test.js
index 723f1bea..4a6c5685 100644
--- a/test/common_test.js
+++ b/test/common_test.js
@@ -315,7 +315,7 @@ function testOrm(schema) {
                 test.ok(post.propertyChanged('content'));
                 post.reload(function (err, post) {
                     test.equal(post.title, 'New title');
-                    test.ok(!post.propertyChanged('title'));
+                    test.ok(!post.propertyChanged('title'), 'title not changed');
                     test.equal(post.content, 'content', 'real value turned back');
                     test.ok(!post.propertyChanged('content'), 'content unchanged');
                     test.done();