Updating from OpenLDAP 2.3.X to 2.4.X
=====================================

Changed Database format:
    Due change in the "BDB"-backend's index database format, existing
    bdb-databases need to be reloaded from LDIF completely. This is
    normally done during the package installation/update. This might not
    work in all setups and for that database dumps of all bdb/hdb
    databases are created during the update. 
    You can find the database dump of each bdb database in the
    database directory for that database (default: /var/lib/ldap/). The
    file name is "ldapbak.ldif.X" where "X" presents the number of the
    database.
    If the database backups where not created during the package update for
    some reason, you can do them manually by using the command:
        /usr/sbin/openldap-2.3-slapcat -T c \
            -f /etc/openldap/schema.backup.XXXXXX/slapd.conf.update
    Before dumping the database you should remove the db's enviroment (the
    __db*-file in /var/lib/ldap)
    To reload the databases please use the tool "slapadd". 

Other Changes:
    For additional information on important changes and upgrade
    instructions, please have a look a the OpenLDAP Administrator's Guide. 
    You can find in at:
    /usr/share/doc/packages/openldap2/guide/admin/guide.html
    or online at:
    http://www.openldap.org/doc/admin24/