XMLRPC does not limit deserializable classes.

I confirmed that the classes that can be generated by parsing the xml sent in the request or response by XMLRPC bundled in ruby are not restricted.

  if Config::ENABLE_MARSHALLING and param.class.included_modules.include? XMLRPC::Marshallable
    # convert Ruby object into Hash
    ret = {"___class___" => param.class.name}
    param.instance_variables.each {|v|