Ok, i did this:
// add_filter('wpcf7_validate_cf7ic*','cf7ic_check_if_spam', 10, 2);
// add_filter('wpcf7_validate_cf7ic','cf7ic_check_if_spam', 10, 2);
add_filter('wpcf7_validate','cf7ic_check_if_spam', 10, 2);
in cf7-image-captcha.php and it works.
