Cannot resolve group example to gid : not found (ldapadduser error)

Hi,

https://help.ubuntu.com/13.10/serverguide/openldap-server.html#openldap-serv...

I'm following the instructions on the following webpage, with the following sections skipped.

- Modifying the slapd Configuration Database - Logging - Replication - Access Control - TLS - Replication and TLS

Then I get the following errors when I try the following commands. I'm know that I might make simple mistakes but I have no clue how to figure it out. Could you help me on how to make the command work? Thanks.

pengy@lithium:/etc/ldap/schema$ sudo ldapadduser george example Cannot resolve group example to gid : not found