def parameters_for_signature
      params = []
      params << options[:parameters].to_query if options[:parameters]

      unless options[:clobber_request]
        params << header_params.to_query
        params << request.query_string unless query_string_blank?

        if request.post? && request.content_type.to_s.downcase.start_with?("application/x-www-form-urlencoded")
          params << request.raw_post
        end
      end

      params.
        join('&').split('&').
        reject { |s| s.match(/\A\s*\z/) }.
        map { |p| p.split('=').map{|esc| CGI.unescape(esc)} }.
        reject { |kv| kv[0] == 'oauth_signature'}
    end
def parameters_for_signature
      params = []
      params << options[:parameters].to_query if options[:parameters]

      unless options[:clobber_request]
        params << header_params.to_query
        params << request.query_string unless query_string_blank?

        if request.post? && request.content_type.to_s.downcase.start_with?("application/x-www-form-urlencoded")
          params << request.raw_post
        end
      end

      params.
        join('&').split('&').
        reject { |s| s.match(/\A\s*\z/) }.
        map { |p| p.split('=').map{|esc| CGI.unescape(esc)} }.
        reject { |kv| kv[0] == 'oauth_signature'}
    end
Override from OAuth::RequestProxy::Base to avoid roundtrip
 conversion to Hash or Array and thus preserve the original
 parameter names