The configuration of OpenLDAP got a bit (more) complicated. cn=config is still used, but when installing the packages from the repositories only a skeleton configuration of openldap is installed. You're not asked anymore to provide a password when the package is installed and issuing the "dpkg-reconfigure slapd" only resets openldap to the skeleton configuration. You will have to set up the openldap database, root dn and acl's yourself using the root account (or sudo) in order to configure openldap. Here is how I configured openldap in Karmic Koala, but I do not issue any guarantee that this setup will suit your needs or works for you as it worked for me.