rubinius/rubinius — pull request #2488 by kachick (2013-07-22 17:07:46+00:00)
Title: {Rational,Complex}#marshal_dump and Time.#{_load,_dump} should be  private methods from 2.0

And looks removed {Rational,Complex}#marshal_load on 2.0.
But I guess the fix requires Module#remove_method as #2480 :<