I am looking at implementing a server for mailinglists.
I have installed mailman and postfix.

The webinterface of mailman seems to work fine. I can send out email from the postfix server too. I have created some lists and added members but when I post a message I get a 550 error:

Recipient address rejected: User unknown in local recipient table

I have specified our smtp server in the postfix file and thats seems to be fine.
However the error occurs when I send an email to one of the lists

Recipient address rejected: User unknown in local recipient table

It must be an incorrect mapping. email to a local account works fine!


here is my main.cf



#
#soft_bounce = no

#
queue_directory = /var/spool/postfix
#
command_directory = /usr/local/sbin
#
daemon_directory = /usr/local/libexec/postfix
#
mail_owner = postfix

#
#default_privs = nobody
#
myhostname = lists.mydomain.com
#
mydomain = mydomain.com
#
myorigin = $myhostname
myorigin = $mydomain
#
inet_interfaces = all
inet_interfaces = $myhostname
inet_interfaces = $myhostname, localhost
#
#proxy_interfaces =
#proxy_interfaces = 1.2.3.4
#
mydestination = $myhostname, localhost.$mydomain, it022607.mydomain.com
#mydestination = $myhostname, localhost.$mydomain, localhost, $mydomain
#mydestination = $myhostname, localhost.$mydomain, localhost, $mydomain,
# mail.$mydomain, www.$mydomain, ftp.$mydomain
#
#local_recipient_maps = unixasswd.byname $alias_maps
#local_recipient_maps = proxy:unixasswd.byname $alias_maps
#local_recipient_maps =
#
unknown_local_recipient_reject_code = 550
#
#mynetworks_style = class
#mynetworks_style = subnet
mynetworks_style = host
#
mynetworks = 130.123.128.0/24, 127.0.0.0/8
#mynetworks = $config_directory/mynetworks
#mynetworks = hash:/usr/local/etc/postfix/network_table
#
#relay_domains = $mydestination
#
relayhost = smtp.mydomain.com
#relayhost = [gateway.my.domain]
#relayhost = [mailserver.isp.tld]
#relayhost = uucphost
#relayhost = [an.ip.add.ress]
#
#alias_maps = dbm:/etc/aliases
alias_maps = hash:/usr/local/mailman/data/aliases
#alias_maps = hash:/etc/aliases, nis:mail.aliases
#alias_maps = netinfo:/aliases
#
#alias_database = dbm:/etc/aliases
#alias_database = dbm:/etc/mail/aliases
#alias_database = hash:/etc/aliases
#alias_database = hash:/etc/aliases, hash:/opt/majordomo/aliases
#
recipient_delimiter = +
#
#home_mailbox = Mailbox
#home_mailbox = Maildir/
#
#mail_spool_directory = /var/mail
#mail_spool_directory = /var/spool/mail
#
#mailbox_command = /some/where/procmail
#mailbox_command = /some/where/procmail -a "$EXTENSION"
#
#mailbox_transport = lmtp:unix:/file/name
#mailbox_transport = cyrus
#
#luser_relay = $user@other.host
#luser_relay = $local@other.host
#luser_relay = admin+$local
#
#fast_flush_domains = $relay_domains
#
#smtpd_banner = $myhostname ESMTP $mail_name
#smtpd_banner = $myhostname ESMTP $mail_name ($mail_version)

#local_destination_concurrency_limit = 2
#default_destination_concurrency_limit = 20
debug_peer_level = 2
#
#debug_peer_list = 127.0.0.1
#debug_peer_list = some.domain


debugger_command =
PATH=/bin:/usr/bin:/usr/local/bin:/usr/X11R6/bin
xxgdb $daemon_directory/$process_name $process_id & sleep 5


#
sendmail_path = /usr/local/sbin/sendmail

# newaliases_path: The full pathname of the Postfix newaliases command.
# This is the Sendmail-compatible command to build alias databases.
#
newaliases_path = /usr/local/bin/newaliases

# mailq_path: The full pathname of the Postfix mailq command. This
# is the Sendmail-compatible mail queue listing command.
#
mailq_path = /usr/local/bin/mailq

# setgid_group: The group for mail submission and queue management
# commands. This must be a group name with a numerical group ID that
# is not shared with other accounts, not even with the Postfix account.
#
setgid_group = maildrop html_directory: The location of the Postfix HTML documentation.
html_directory = no
manpage_directory: The location of the Postfix on-line manual pages.
manpage_directory = /usr/local/man
sample_directory: The location of the Postfix sample configuration files.
This parameter is obsolete as of Postfix 2.1.
sample_directory = /usr/local/etc/postfix
readme_directory = no