diff --git a/lib/class.js b/lib/class.js
index ff9d7bd..f1ba4e9 100644
--- a/lib/class.js
+++ b/lib/class.js
@@ -217,7 +217,8 @@ var extend = ( function( extending )
                 prototype, prototype, prototype
             ),
 
-            abstract_methods = util.clone( base.abstractMethods )
+            abstract_methods =
+                util.clone( getMeta( base.__cid ).abstractMethods )
                 || { __length: 0 }
         ;
 
@@ -303,7 +304,8 @@ var extend = ( function( extending )
         util.freeze( new_class );
 
         // create internal metadata for the new class
-        createMeta( new_class, base.prototype.__cid );
+        var meta = createMeta( new_class, base.prototype.__cid );
+        meta.abstractMethods = abstract_methods;
 
         // we're done with the extension process
         extending = false;
@@ -512,11 +514,6 @@ function attachAbstract( func, methods )
     {
         return is_abstract;
     });
-
-    // attach the list of abstract methods to the class (make the copy of the
-    // methods to ensure that they won't be gc'd or later modified and screw up
-    // the value)
-    util.defineSecureProp( func, 'abstractMethods', methods );
 }
 
 
@@ -627,6 +624,8 @@ function createMeta( func, parent_id )
             implemented: [],
         };
     }
+
+    return class_meta[ id ];
 }
 
 
@@ -642,6 +641,6 @@ function createMeta( func, parent_id )
  */
 function getMeta( id )
 {
-    return class_meta[ id ];
+    return class_meta[ id ] || {};
 }