the way I did is just remove some code from Login.inc.php.
and change some words in language pack

includes/login.inc.php
find
**************************************************
if(trim($feld["activate_code"]) != '')
{
header("location: index.php?mode=login&login_message=account_not_activated");
exit;
}
**************************************************
and just remove it.

so after user registed, don't show the message about send an activate code. give a link of LOGIN. And when new ID login, won't show up an message ID is not activated.

That's what I figout in a stupid way...but it works...