Ok, I was able to solve this one. I read the following post:
http://www.zimbra.com/forums/adminis...-solution.html
But didn't quite understand what was actually contained in the ldap.bak file referenced. Didn't know if it was a single file or it was the whole openldap directory or some sort of ldap export or what.
So I took the easy route wiped out and restored the openldap-data and openldap directories from backup, changed the ownership of all the restored files to zimbra:zimbra and was able to start zimbra after that.
Whew!