Dapet dari milis gosa@oss.gonicus.de 
Just an example. You need to include something like this. It is no complete main.cf and
it has to be adapted to fit your needs. Especially the insiders stuff – if you need it.
# Virtual source virtualsource_server_host = 10.3.66.11 virtualsource_search_base = dc=gonicus,dc=de virtualsource_query_filter = (&(|(mail=%s)(gosaMailAlternateAddress=%s))(objectClass=gosaAccount)) virtualsource_result_attribute = uid,gosaMailForwardingAddress # Shared Folder + Aliases + Forwardings sharedsource_server_host = 10.3.66.11 sharedsource_search_base = dc=gonicus,dc=de sharedsource_query_filter = (&(|(mail=%s)(gosaMailAlternateAddress=%s))(objectClass=posixGroup)) sharedsource_result_attribute = gosaSharedFolderTarget,gosaMailForwardingAddress # Access Lists for Non Local Delivery acllocal_server_host = 10.3.66.11 acllocal_search_base = dc=gonicus,dc=de acllocal_query_filter = (&(|(mail=%s)(gosaMailAlternateAddress=%s))(gosaMailDeliveryMode=*L*)) acllocal_result_attribute = mail acllocal_result_filter = insiders_only # Map definition virtual_maps = ldap:virtualsource, ldap:sharedsource # For local only delivery smtpd_restriction_classes = insiders_onlyfallback_transport = smtp mailbox_transport = lmtp:unix:/var/lib/imap/socket/lmtp insiders_only = check_sender_access regexp:/etc/postfix/insiders, reject # For lmtp delivery fallback_transport = smtp mailbox_transport = lmtp:unix:/var/lib/imap/socket/lmtp