right after i configured zimbra-proxy with libexec/zmproxyconfig -e -w -H mta2.mydomain.com

but proxy service cannot be started

Code:
$ zmcontrol restart
Host mta2.mydomain.com
	Stopping zmconfigd...Done.
	Stopping stats...Done.
	Stopping mta...Done.
	Stopping spell...Done.
	Stopping snmp...Done.
	Stopping cbpolicyd...Done.
	Stopping archiving...Done.
	Stopping antivirus...Done.
	Stopping antispam...Done.
	Stopping imapproxy...Done.
	Stopping memcached...Done.
	Stopping mailbox...Done.
	Stopping logger...Done.
	Stopping ldap...Done.
Host mta2.mydomain.com
	Starting ldap...Done.
	Starting zmconfigd...Done.
	Starting imapproxy...Failed.
Starting nginx...nginx: [emerg] socket() [::]:143 failed (97: Address family not supported by protocol)
failed.


	Starting antispam...Done.
	Starting antivirus...Done.
	Starting snmp...Done.
	Starting mta...Failed.
postalias: fatal: bad string length 0 < 1: inet_protocols = 
postfix failed to start
Starting saslauthd...done.


	Starting stats...Done.
any extra step(s) that i should've done?