In article <486CB4DC.4030608 / ruby-lang.org>,
  Urabe Shyouhei <shyouhei / ruby-lang.org> writes:

> Thank you, I merged this revision into 1.8.7.

It causes following problem.

% ./ruby -rsingleton -ve '
class C
  include Singleton
end
m = Marshal.dump(C.instance)
p Marshal.load(m)
'
ruby 1.8.6 (2008-07-02 patchlevel 264) [i686-linux]
-e:6:in `load': class C needs to have method `_load' (TypeError)
        from -e:6

r16659 is also required.

Note that r16659 causes RubySpec failure, it is another
RubySpec bug.
-- 
Tanaka Akira