class ActiveFedora::MetadataDatastream

def to_xml(xml = REXML::Document.new("<fields />")) #:nodoc:
  fields.each_pair do |field,field_info|
    el = REXML::Element.new("#{field.to_s}")
      if field_info[:element_attrs]
        field_info[:element_attrs].each{|k,v| el.add_attribute(k.to_s, v.to_s)}
      end
    field_info[:values].each do |val|
      el = el.clone
      el.text = val.to_s
      if xml.class == REXML::Document
        xml.root.elements.add(el)
      else
        xml.add(el)
      end
    end
  end
  return xml.to_s
end