Yes, Iam using ZCS 5.X. Here is auth settings:
[zimbra@mail root]$ zmprov getServer mail.trustbank.com.vn | grep Auth
zimbraMtaAuthEnabled: TRUE
zimbraMtaAuthHost: mail.trustbank.com.vn
zimbraMtaAuthTarget: TRUE
zimbraMtaAuthURL:
http://mail.trustbank.com.vn/service/soap/
zimbraMtaTlsAuthOnly: TRUE
is it ok? and what I have to do now?