Hello guys, I have a problem in receive e-mail.
I can send e-mail, works fine, but if I try to send a e-mail it returns saying:

Delivery to the following recipient failed permanently:

     luiz@nudestay.com.br

Technical details of permanent failure:
DNS Error: Domain name not found

I don't know why, last weak everything works, now it stopped to receive e-mail.

Could you help-me to solve this problem?
Probably are another stupid simple mistake in configuration...

Thanks for the help!

==== Required information ====
- iRedMail version: 0.8.4
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): mysql
- Linux/BSD distribution name and version: ubuntu 12.04 server x64
- Related log if you're reporting an issue:
Jun 16 19:56:08 localhost postfix/error[1790]: C04A260CC5: to=<root@nudemail.tk>, relay=none, delay=44463, delays=44463/0.01/0/0.01, dsn=4.3.0, status=deferred (mail transport unavailable)
Jun 16 19:56:08 localhost postfix/error[1791]: 0B94260CDC: to=<root@nudemail.tk>, relay=none, delay=44459, delays=44459/0.01/0/0, dsn=4.3.0, status=deferred (mail transport unavailable)
Jun 16 19:56:09 localhost postfix/smtpd[1783]: connect from localhost[127.0.0.1]
Jun 16 19:56:09 localhost postfix/smtpd[1783]: warning: connect to 127.0.0.1:10031: Connection refused
Jun 16 19:56:09 localhost postfix/smtpd[1783]: warning: problem talking to server 127.0.0.1:10031: Connection refused
Jun 16 19:56:10 localhost postfix/smtpd[1783]: warning: connect to 127.0.0.1:10031: Connection refused
Jun 16 19:56:10 localhost postfix/smtpd[1783]: warning: problem talking to server 127.0.0.1:10031: Connection refused
Jun 16 19:56:10 localhost postfix/smtpd[1783]: NOQUEUE: reject: RCPT from localhost[127.0.0.1]: 451 4.3.5 Server configuration problem; from=<conta@nudestay.com.br> to=<jacksonbenete@gmail.com> proto=ESMTP helo=<nudemail.tk>
Jun 16 19:56:10 localhost roundcube: SMTP Error: SMTP error: Failed to add recipient 'jacksonbenete@gmail.com' in /usr/share/apache2/roundcubemail-0.8.6/program/include/main.inc on line 1485 (POST /mail/?_unlock=loading1371412569385&_lang=undefined?_task=mail&_action=send)
Jun 16 19:56:10 localhost postfix/smtpd[1783]: disconnect from localhost[127.0.0.1]
Jun 16 20:00:43 localhost postfix/smtpd[1813]: connect from mail-bk0-f54.google.com[209.85.214.54]
Jun 16 20:00:44 localhost postfix/smtpd[1813]: warning: connect to 127.0.0.1:10031: Connection refused
Jun 16 20:00:44 localhost postfix/smtpd[1813]: warning: problem talking to server 127.0.0.1:10031: Connection refused
Jun 16 20:00:45 localhost postfix/smtpd[1813]: warning: connect to 127.0.0.1:10031: Connection refused
Jun 16 20:00:45 localhost postfix/smtpd[1813]: warning: problem talking to server 127.0.0.1:10031: Connection refused
Jun 16 20:00:45 localhost postfix/smtpd[1813]: NOQUEUE: reject: RCPT from mail-bk0-f54.google.com[209.85.214.54]: 451 4.3.5 Server configuration problem; from=<jacksonbenete@gmail.com> to=<conta@nudestay.com.br> proto=ESMTP helo=<mail-bk0-f54.google.com>
Jun 16 20:00:45 localhost postfix/smtpd[1813]: disconnect from mail-bk0-f54.google.com[209.85.214.54]
Jun 16 20:01:08 localhost postfix/qmgr[15728]: 6D3BF61169: from=<www-data@nudemail.tk>, size=896, nrcpt=1 (queue active)
Jun 16 20:01:08 localhost postfix/qmgr[15728]: warning: connect to transport private/smtp-amavis: No such file or directory
Jun 16 20:01:08 localhost postfix/error[1825]: 6D3BF61169: to=<contato@nudestay.com.br>, relay=none, delay=936, delays=936/0.01/0/0.01, dsn=4.3.0, status=deferred (mail transport unavailable)
Jun 24 18:31:08 localhost postfix/smtpd[30005]: connect from localhost[127.0.0.1]
Jun 24 18:31:08 localhost postfix/smtpd[30005]: AED99614BF: client=localhost[127.0.0.1]
Jun 24 18:31:08 localhost postfix/cleanup[29993]: AED99614BF: message-id=<e7f8480c2903f738a487c04a3d9187ea@nudestay.com.br>
Jun 24 18:31:08 localhost postfix/qmgr[1370]: AED99614BF: from=<luiz@nudestay.com.br>, size=969, nrcpt=1 (queue active)
Jun 24 18:31:08 localhost postfix/smtpd[30005]: disconnect from localhost[127.0.0.1]
Jun 24 18:31:08 localhost amavis[1123]: (01123-12) Passed CLEAN, MYNETS LOCAL [127.0.0.1] [127.0.0.1] <luiz@nudestay.com.br> -> <jacksonbenete@gmail.com>, Message-ID: <e7f8480c2903f738a487c04a3d9187ea@nudestay.com.br>, mail_id: B2ji8yh0go2u, Hits: -8.82, size: 535, queued_as: AED99614BF, 1242 ms
Jun 24 18:31:08 localhost postfix/smtp[29999]: 548E160CB9: to=<jacksonbenete@gmail.com>, relay=127.0.0.1[127.0.0.1]:10024, delay=5, delays=3.4/0.21/0.5/0.93, dsn=2.0.0, status=sent (250 2.0.0 from MTA([127.0.0.1]:10025): 250 2.0.0 Ok: queued as AED99614BF)
Jun 24 18:31:08 localhost postfix/qmgr[1370]: 548E160CB9: removed
Jun 24 18:31:09 localhost postfix/smtp[30006]: AED99614BF: to=<jacksonbenete@gmail.com>, relay=gmail-smtp-in.l.google.com[173.194.73.26]:25, delay=0.98, delays=0.01/0.01/0.21/0.75, dsn=2.0.0, status=sent (250 2.0.0 OK 1372098669 cf3si5220299vcb.26 - gsmtp)
Jun 24 18:31:09 localhost postfix/qmgr[1370]: AED99614BF: removed

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