class CFPropertyList::CFString

It will convert the value to UTF-16BE if necessary (i.e. if non-ascii char contained)
This class holds string values, both, UTF-8 and UTF-16BE

def to_binary(bplist)

convert to binary 
def to_binary(bplist)
  return bplist.string_to_binary(@value);
end

def to_xml

convert to XML 
def to_xml
  n = LibXML::XML::Node.new('string')
  n << LibXML::XML::Node.new_text(@value) unless @value.nil?
  return n
end