postfix的邮件投递问题

wwdmmy

我的postfix可以收到邮件，邮件能进入incoming 队列，但是不能被投递到本地用户的邮箱中。用mailq命令可以看见邮件列表。
我看了日志如下：
Mar 16 14:02:48 mail postfix/qmgr[2439]: E0EE533E6B: from=<weimanyi1980@163.com>, size=1578, nrcpt=1 (queue active)
Mar 16 14:03:18 mail postfix/smtp[2473]: connect to mail.ndcnc.gov.cn[202.108.111.15]: Connection timed out (port 25)
Mar 16 14:03:18 mail postfix/smtp[2473]: E0EE533E6B: to=<weidx@mail.ndcnc.gov.cn>, relay=none, delay=2047, delays=2017/0.03/30/0, dsn=4.4.1, status=deferred (connect to mail.ndcnc.gov.cn[202.108.111.15]: Connection timed out)

我的postfix配置文件内容是：

alias_database = hash:/etc/aliases.db
alias_maps = hash:/etc/aliases
command_directory = /usr/sbin
config_directory = /etc/postfix
daemon_directory = /usr/libexec/postfix
debug_peer_level = 2
default_destination_concurrency_limit = 10
disable_dns_lookups = yes
inet_interfaces = all
local_destination_concurrency_limit = 2
local_recipient_maps = $alias_maps unix:passwd.byname
mail_owner = postfix
mail_spool_directory = /var/spool/mail
mailbox_command = /usr/bin/procmail
mydestination = $mydomain
mydomain = ndcnc.gov.cn
myhostname = mail.ndcnc.gov.cn
mynetworks = 202.108.0.0/16
myorigin = $mydomain
queue_directory = /var/spool/postfix
relay_domains = $mydomain
smtpd_banner = $myhostname ESMTP $mail_name

请问大虾这是什么问题，怎么解决？郁闷死我了，搞了一个下午也不知道原因。我怀疑是本地的MDA有问题，但无从下手，高手帮帮我！谢谢