diff --git a/ChangeLog b/ChangeLog
index f1a36a080c..99bc01acc9 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Sat Mar  9 11:58:39 2013  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* marshal.c (w_extended): check for prepended object.
+	  [ruby-core:53206] [Bug #8043]
+
 Sat Mar  9 08:36:58 2013  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* load.c (features_index_add_single, rb_feature_p): store single index
diff --git a/marshal.c b/marshal.c
index 7b45d1c835..9ec1f9400f 100644
--- a/marshal.c
+++ b/marshal.c
@@ -457,12 +457,17 @@ hash_each(VALUE key, VALUE value, struct dump_call_arg *arg)
     return ST_CONTINUE;
 }
 
+#define SINGLETON_DUMP_UNABLE_P(klass) \
+    (RCLASS_M_TBL(klass)->num_entries || \
+     (RCLASS_IV_TBL(klass) && RCLASS_IV_TBL(klass)->num_entries > 1))
+
 static void
 w_extended(VALUE klass, struct dump_arg *arg, int check)
 {
     if (check && FL_TEST(klass, FL_SINGLETON)) {
-	if (RCLASS_M_TBL(klass)->num_entries ||
-	    (RCLASS_IV_TBL(klass) && RCLASS_IV_TBL(klass)->num_entries > 1)) {
+	VALUE origin = RCLASS_ORIGIN(klass);
+	if (SINGLETON_DUMP_UNABLE_P(klass) ||
+	    (origin != klass && SINGLETON_DUMP_UNABLE_P(origin))) {
 	    rb_raise(rb_eTypeError, "singleton can't be dumped");
 	}
 	klass = RCLASS_SUPER(klass);
diff --git a/test/ruby/marshaltestlib.rb b/test/ruby/marshaltestlib.rb
index 45c94e0f15..665d365a9a 100644
--- a/test/ruby/marshaltestlib.rb
+++ b/test/ruby/marshaltestlib.rb
@@ -365,6 +365,11 @@ module MarshalTestLib
     o = Object.new
     def o.m() end
     assert_raise(TypeError) { marshaltest(o) }
+
+    bug8043 = '[ruby-core:53206] [Bug #8043]'
+    class << o; prepend Mod1; end
+    assert_raise(TypeError, bug8043) {marshaltest(o)}
+
     o = Object.new
     c = class << o
       @v = 1