# File lib/dnsruby/code_mappers.rb, line 54
    def unknown_string(arg)
      if (arg=~/^CLASS/i)
        Classes.add_pair(arg, arg.gsub('CLASS', '').to_i)
        set_string(arg)
      else
        raise ArgumentError.new("String #{arg} not a member of #{self.class}")
      end
    end