Unverified users getting confused

I am using the email verification feature. I love this feature but it’s sorely missing 1 feature; when an unverified user attempts to log in it tells them they’re unverified and to check their email. I’ve got multiple users that decided to register an account and get the verification email. This works. However, sometimes they don’t check their email and don’t verify themselves.

I don’t see an option in the theme UI to enable this feature so I’m asking for some hints about where to check for this in PHP. I’ve spent hours tinkering around with the code and can’t figure out the best place to enable this custom login error if a user attempts to login with an unverified account.

Can someone please point me in the right direction as to where to insert this?

http://wordpress.org/plugins/pie-register/