DDS incompatible with shadow

Hi, if have just setup a provider with 2.4.7 and a consumer with 2.4.7, db4.5. The provider is running, when starting the empty consumer I get

slapd startup: initiated. backend_startup_one: starting "cn=config" config_back_db_open backend_startup_one: starting "o=avci,c=de" hdb_db_open: "o=avci,c=de" hdb_db_open: database "o=avci,c=de": dbenv_open(/opt/openldap/var/openldap-data/). DDS incompatible with shadow database "o=avci,c=de". backend_startup_one: bi_db_open failed! (1) slapd shutdown: initiated ====> bdb_cache_release_all ====> bdb_cache_release_all slapd destroy: freeing system resources. slapd stopped.

what is DDS?

-Dieter