In presence_candidates(), always return a full match for objectClass.

servers/slapd/back-bdb/filterindex.c

@@ -191,6 +191,7 @@ presence_candidates(
 	AttributeDescription *desc,
 	ID *ids )
 {
+	struct bdb_info *bdb = (struct bdb_info *) be->be_private;
 	DB *db;
 	int rc;
 	slap_mask_t mask;
@@ -198,6 +199,11 @@ presence_candidates(
 
 	Debug( LDAP_DEBUG_TRACE, "=> bdb_presence_candidates\n", 0, 0, 0 );
 
+	if( desc == slap_schema.si_ad_objectClass ) {
+		BDB_IDL_ALL( bdb, ids );
+		return 0;
+	}
+
 	rc = bdb_index_param( be, desc, LDAP_FILTER_PRESENT,
 		&db, &mask, &prefix );
 

servers/slapd/back-ldbm/filterindex.c

@@ -223,6 +223,10 @@ presence_candidates(
 
 	idl = idl_allids( be );
 
+	if( desc == slap_schema.si_ad_objectClass ) {
+		return idl;
+	}
+
 	rc = index_param( be, desc, LDAP_FILTER_PRESENT,
 		&dbname, &mask, &prefix );