    # File lib/rmail/address.rb, line 167
        def comments=(comments)
          case comments
          when nil
            @comments = comments
          when Array
            @comments = comments
          when String
            @comments = [ comments ]
          else
            raise TypeError, "Argument to RMail::Address#comments= must be " +
              "String, Array or nil, was #{comments.type}."
          end
          @comments.freeze
        end