1-
PHP Code:
if (strtolower(substr($email,-4))!='.gov' AND strtolower(substr($email,-4))!='.mil')
{
eval("standarderror(\"".gettemplate("email_notallowed")."\");"); exit;
}
2- If you want to restrict registrations to 200 domains of your choice, well it is not possible with a few lines of code like in this hack. You either need to enter them one by one in the code which wouldn't be handy (especially when you need to modify them later), or you need a more sophisticated hack which is not a 2 min job.