# File lib/em/protocols/smtpserver.rb, line 377
377:       def process_rcpt_to rcpt
378:         unless @state.include?(:mail_from)
379:           send_data "503 MAIL is required before RCPT\r\n"
380:         else
381:           succeeded = proc {
382:             send_data "250 Ok\r\n"
383:             @state << :rcpt unless @state.include?(:rcpt)
384:           }
385:           failed = proc {
386:             send_data "550 recipient is unacceptable\r\n"
387:           }
388: 
389:           d = receive_recipient rcpt
390: 
391:           if d.respond_to?(:set_deferred_status)
392:             d.callback(&succeeded)
393:             d.errback(&failed)
394:           else
395:             (d ? succeeded : failed).call
396:           end
397: 
398: ??
399:         end
400:       end