Add Text Below Signup Submit Button - Anti-Splot

I want to add a comment below the New Site Signup Button that says, "Be sure to check your email (and Spam folder) for the activation code."

I am using Anti-Splog and the Rename wp-signup.php feature. I read that this is possible using hooks in Anti-Splog, but I'm not sure how to go about finding the hooks or creating the code for functions.php.

Your helps is appreciated.

Thanks,
Chris