# File lib/gdata/auth/authsub.rb, line 97
      def upgrade
        request = GData::HTTP::Request.new(SESSION_HANDLER)
        sign_request!(request)
        service = GData::HTTP::DefaultService.new
        response = service.make_request(request)
        if response.status_code != 200
          raise GData::Client::AuthorizationError.new(response)
        end
        
        @token = response.body[/Token=(.*)/,1]
        return @token
        
      end