I know you are suppose to make changes through the command line, when using cn=config. I tried changing it through ldapmodify, however wasn't able to get it to work. So changed it in the file and it did work. We are transitioning away from cn=config, so this is just a short term solution.
Bad idea, given that cn=config will eventually become the only way to configure openldap. Instead of transitioning away, you should figure out why you have problems using it, and resolve those instead.
--Quanah -- Quanah Gibson-Mount Architect - Server Zimbra, Inc. -------------------- Zimbra :: the leader in open source messaging and collaboration