I have set up Zimbra in a small office that uses IPCop as a firewall and proxy server. IPCop allows authentication through an external LDAP. I would like to use Zimbra as the external LDAP. I have attached an image of the IPCop fields that are required to get this working. I wasn't sure if Zimbra uses LDAP Version 2 or Version 3. I did find that port 389 is the appropriate port. I need to know what to use for the BASE DN and if the LDAP Server is simply the hostname / IP of my Zimbra server. I would appreciate any help in this area.