We highly recommend this to 8.0.0 users for the upgrade to OpenLDAP 2.4.33 (77389 & 77953)
An LDAP database reload is automatically preformed when upgrading from 8.0.0 to avoid some previous corruption.
This is the primary intent of the 8.0.1 maintenance release; 8.0.2 is on schedule with over 400 tickets.
Network Edition Downloads & Release Notes | Open Source Edition Downloads & Release Notes | Appliance Edition Downloads & Release Notes
If you're coming from the 7.x or 6.x branch here's an intro to Zimbra 8!