replaced zabbix-server from 2.0.3 to 2.0.4
start to replace frontend, deleted older folder, copied new one.
reload page in browser -> it opened /setup.php, ok, let's redo it again.
when i got to testing connection i get following error -> error 500.
in apache2 error.log there is

PHP Fatal error:  Call to undefined function zbx_dbstr() in /var/www/monitoring/include/db.inc.php on line 126, referer: http://DOMAIN/setup.php