Hello Everyone.
I have a domain name public is: abc.com. In cpanel:
I created A record is mail.abc.com and pointed to IP pubic 2.3.4.5.
I created MX record and pointed mail.abc.com.
After in CentOS 6.3, I configured:
ip private 192.168.1.244/24
in file /etc/hosts: 192.168.1.244 mail.abc.com mail
hostname: mail.abc.com
in file /etc/resolv.conf: nameserver 8.8.8.8
I used tool nslookup and resolved domain abc.com. Then I installed zimbra with 7.2.1 Open source in centos 6.3 x86_64. I install everyone expected zimbra-proxy After finish this installation, I create to mailbox u1@abc.com and u2@abc.com. When I send mail from u1 to u2 and cc for u1, I didn't see email to u1. I see /var/log/maillog and I see:

Oct 25 14:22:19 mail postfix/qmgr[35327]: 3E2CB16310C: from=<user1@abc.com>, size=1297, nrcpt=2 (queue active)
Oct 25 14:22:19 mail postfix/smtp[52317]: 49D3D163108: to=<u1@abc.com>, relay=127.0.0.1[127.0.0.1]:10024, delay=1, delays=0.09/0.04/0.06/0.83, dsn=2.0.0, status=sent (250 2.0.0 from MTA([127.0.0.1]:10025): 250 2.0.0 Ok: queued as 3E2CB16310C)
Oct 25 14:22:19 mail postfix/smtp[52317]: 49D3D163108: to=<u2@abc.com>, relay=127.0.0.1[127.0.0.1]:10024, delay=1, delays=0.09/0.04/0.06/0.83, dsn=2.0.0, status=sent (250 2.0.0 from MTA([127.0.0.1]:10025): 250 2.0.0 Ok: queued as 3E2CB16310C)
Oct 25 14:22:19 mail postfix/qmgr[35327]: 49D3D163108: removed
Oct 25 14:22:19 mail postfix/error[52321]: 3E2CB16310C: to=<u1@abc.com>, relay=none, delay=0.08, delays=0.01/0.06/0/0.01, dsn=5.0.0, status=bounced (abc.com)
Oct 25 14:22:19 mail postfix/error[52321]: 3E2CB16310C: to=<u2@abc.com>, relay=none, delay=0.08, delays=0.01/0.06/0/0.01, dsn=5.0.0, status=bounced (abc.com)

Oct 25 14:23:22 mail postfix/lmtp[52324]: connect to mail.abc.com[2.3.4.5]:7025: Connection timed out
Oct 25 14:23:22 mail postfix/lmtp[52324]: 5669E163110: to=<user1@abc.com>, relay=none, delay=63, delays=0/0.01/63/0, dsn=4.4.1, status=deferred (connect to mail.abc.com[2.3.4.5]:7025: Connection timed out)

Please help me to fix it. Thanks so much