protected function setAttributes($attributes = null)
    {
        /*
        * fetch attributes from the server
        */
        if (is_null($attributes) && is_resource($this->_entry) && is_resource($this->_link)) {
            // fetch schema
            if ($this->_ldap instanceof Net_LDAP2) {
                $schema = $this->_ldap->schema();
            }
            // fetch attributes
            $attributes = array();
            do {
                if (empty($attr)) {
                    $ber  = null;
                    $attr = @ldap_first_attribute($this->_link, $this->_entry, $ber);
                } else {
                    $attr = @ldap_next_attribute($this->_link, $this->_entry, $ber);
                }
                if ($attr) {
                    $func = 'ldap_get_values'; // standard function to fetch value

                    // Try to get binary values as binary data
                    if ($schema instanceof Net_LDAP2_Schema) {
                        if ($schema->isBinary($attr)) {
                             $func = 'ldap_get_values_len';
                        }
                    }
                    // fetch attribute value (needs error checking?)
                    $attributes[$attr] = $func($this->_link, $this->_entry, $attr);
                }
            } while ($attr);
        }

        /*
        * set attribute data directly, if passed
        */
        if (is_array($attributes) && count($attributes) > 0) {
            if (isset($attributes["count"]) && is_numeric($attributes["count"])) {
                unset($attributes["count"]);
            }
            foreach ($attributes as $k => $v) {
                // attribute names should not be numeric
                if (is_numeric($k)) {
                    continue;
                }
                // map generic attribute name to real one
                $this->_map[strtolower($k)] = $k;
                // attribute values should be in an array
                if (false == is_array($v)) {
                    $v = array($v);
                }
                // remove the value count (comes from ldap server)
                if (isset($v["count"])) {
                    unset($v["count"]);
                }
                $this->_attributes[$k] = $v;
            }
        }

        // save a copy for later use
        $this->_original = $this->_attributes;
    }