/**
  * Unbind from the LDAP server.
  *
  * @return boolean
  *   TRUE on success
  *
  * @throw SimpleLdapException
  */
 public function unbind()
 {
     if ($this->bound) {
         SimpleLdap::ldap_unbind($this->resource);
         $this->bound = FALSE;
     }
     return TRUE;
 }