@SuppressWarnings("unchecked")
  @Override
  public List<Person> searchForPersons(String keyword) {
    String filter =
        "(&(samAccountType=805306368)(|(sn="
            + keyword
            + "*)(givenname="
            + keyword
            + "*)(mail="
            + keyword
            + "*)))";

    logger.debug("filter:" + filter);

    List<Person> persons =
        (List<Person>) ldapTemplate.search("", filter, new PersonAttributesMapper());

    persons.remove(null);
    if (logger.isTraceEnabled()) {
      for (Person p : persons) {
        if (p != null) {
          logger.trace("username: "******"; sap:" + p.getSap());
        }
      }
    }
    return persons;
  }