Regardless if the email is wrong, the function will not return an error because of an invalid email, sorry, but it just wont.
The only possible ways I can see you getting an error is if SMTP is not configured properly on your server. You would need SMTP configured properly for the mail() function to work.
You should try to find a host that supports it.
Also, check to see in the PHP Info that it is supported using this script.
<?phpphpinfo();?>
save that as phpinfo.php and upload it to your host and find the area that mentions SMTP
You will have to contact your hosting admin to find out if it is enabled.
I can't say 100% that everything I said is correct because it has been a while since I have had this problem.

Jeff.