URGENT! Email restriction !!!

Hi, 

I have a very urgent question, it should not be too hard, but I have limited knowledge on permissions.

I would like to allow only people with certain emails to register e.g. email accounts with extension @school.gov

Would it work if I do the following? Go to Admin > Builders > Profile Filds > Join Form - Email - Advanced and then edit the following lines:

return (bool) preg_match('/^([a-z0-9\+\_\-\.]+)@([a-z0-9\+\_\-\.]+)$/i', $arg0);

and change it to:

return (bool) preg_match('/^([a-z0-9\+\_\-\.]+)@([school.gov]+)$/i', $arg0);

I tried it, but nothing happened.

You might consider converting this function http://www.boonex.com/forums/topic/join-form-not-submiting-only-works-when-removing-email-block.htm from listing "forbidden" email domains that are excluded... to listing "allowed" email domains that are ONLY included.