diff --git a/ChangeLog b/ChangeLog
index d25ab986b3..2061a51323 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Fri Sep 13 00:57:54 2013  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* class.c (method_entry_i): should exclude refined methods from
+	  instance method list.  [ruby-core:57080] [Bug #8881]
+
 Fri Sep 13 00:33:09 2013  Charlie Somerville  <charliesome@ruby-lang.org>
 
 	* vm_eval.c (vm_call0): fix prototype, the id parameter should be of
diff --git a/class.c b/class.c
index 25e732ac2e..764c251d5e 100644
--- a/class.c
+++ b/class.c
@@ -989,6 +989,10 @@ method_entry_i(st_data_t key, st_data_t value, st_data_t data)
     st_table *list = (st_table *)data;
     long type;
 
+    if (me && me->def->type == VM_METHOD_TYPE_REFINED) {
+	me = rb_resolve_refined_method(Qnil, me, NULL);
+	if (!me) return ST_CONTINUE;
+    }
     if (!st_lookup(list, key, 0)) {
 	if (UNDEFINED_METHOD_ENTRY_P(me)) {
 	    type = -1; /* none */
diff --git a/test/ruby/test_refinement.rb b/test/ruby/test_refinement.rb
index b6bdc9430f..acca7c04ce 100644
--- a/test/ruby/test_refinement.rb
+++ b/test/ruby/test_refinement.rb
@@ -847,6 +847,17 @@ class TestRefinement < Test::Unit::TestCase
     RUBY
   end
 
+  def test_instance_methods
+    bug8881 = '[ruby-core:57080] [Bug #8881]'
+    assert_not_include(Foo.instance_methods(false), :z, bug8881)
+    assert_not_include(FooSub.instance_methods(true), :z, bug8881)
+  end
+
+  def test_method_defined
+    assert_not_send([Foo, :method_defined?, :z])
+    assert_not_send([FooSub, :method_defined?, :z])
+  end
+
   private
 
   def eval_using(mod, s)
diff --git a/version.h b/version.h
index ddf4a211fe..536980f69f 100644
--- a/version.h
+++ b/version.h
@@ -1,6 +1,6 @@
 #define RUBY_VERSION "2.0.0"
 #define RUBY_RELEASE_DATE "2013-09-13"
-#define RUBY_PATCHLEVEL 306
+#define RUBY_PATCHLEVEL 307
 
 #define RUBY_RELEASE_YEAR 2013
 #define RUBY_RELEASE_MONTH 9