Here's my problem: I want to catch the error thrown when a required field is not filled (or some other type of error) and display the error myself (in my template, or an alert or something). I just don't want the user the be redirected to the error page displayed by wp_die().
I've some people edit a file in wp-include (http://wordpress.org/support/topic/custom-comment-error-page), but I'd like to edit the files as less as possible so I don't run into problems when I update WP.
Anyone have an idea?
Thanks a lot!