hi guys, i got a zimbra 5.0.5 installed and working fine, but beacuse a policy issue i have to change some passwords on my systems, i want to know how to acopmplish it on zimbra, well ldap, mysql and admin users are easy but i can't find information about this:

LDAP Replication password
LDAP Postfix password
LDAP Amavis password

also i want to know how to change hostnames on a multi server installation ( i don't have to do it now, i'm just curious) i mean fot instance how to change ldap hostname on my mailbox server or my mta auth server on my mta server, i'll appreciatte any help on this guys thanks