Hello,
There has been some changes in the way errors are handled in wp-login.php : in WP 2.3.x, there was a global array defined ($errors[]) which could be interacted with via plugins :
$errors['user_email'] = __('<strong>ERROR</strong>: The email address
is not correct.');
With WP2.5, plugins can't seem to add to $errors->add(). I think I've
tried every possibility and I cannot make out why in a plugin
something like :
$errors->add('invalid_email', __('<strong>ERROR</strong>: The email
address is not correct.'));
does not work. I should say that it is part of a function that is inserted through add_action('register_post').
Add that line make wp-login.php go blank.