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# File lib/rmail/message.rb, line 141
    def get_delimiters
      unless multipart? and @delimiters and @delimiters_boundary and
          @delimiters.length == @body.length + 1 and
          header.param('content-type', 'boundary') == @delimiters_boundary
        @delimiters = nil
        @delimiters_boundary = nil
      end
      [ @delimiters, @delimiters_boundary ]
    end