diff --git a/test/ruby/test_module.rb b/test/ruby/test_module.rb
index aa48e1793c..d7a6248909 100644
--- a/test/ruby/test_module.rb
+++ b/test/ruby/test_module.rb
@@ -1290,4 +1290,13 @@ class TestModule < Test::Unit::TestCase
     o.singleton_class.class_eval {prepend Module.new}
     assert_equal([], o.singleton_methods)
   end
+
+  def test_prepend_remove_method
+    assert_raise(NameError) do
+      Class.new do
+        prepend Module.new {def foo; end}
+        remove_method(:foo)
+      end
+    end
+  end
 end
diff --git a/vm_method.c b/vm_method.c
index 5a7722cd67..7546a1c31c 100644
--- a/vm_method.c
+++ b/vm_method.c
@@ -452,6 +452,7 @@ remove_method(VALUE klass, ID mid)
     st_data_t key, data;
     rb_method_entry_t *me = 0;
 
+    klass = RCLASS_ORIGIN(klass);
     if (klass == rb_cObject) {
 	rb_secure(4);
     }