undefined method for enumerable

http://wiki.radiantcms.org/undefined_method_for_enumerable

undefined method `[]' for #<Enumerable::Enumerator:0x........> 

unless '1.9'.respond_to?(:force_encoding)
  String.class_eval do
    begin
      remove_method :chars
    rescue NameError
      # OK
    end
  end
end