if i do have the time to update this hack, ill look into the banned email addresses.
bots cant bypass the captcha, as for emails if the "spammer" is determined he will just find the list of emails that are OK. But i will look into adding the check. I do know that spammers do use temp email services, such as
http://2prong.com/ which is a great service

(they make a new domain like every day).