Custom post type support

Hello, I’m trying to add a custom-post type notification as described here So far, nothing shows up in the list of post I can subscribe to.
I’m using a theme that comes with a pre-installed “portfolio” custom post type. I renamed it in the theme option to fit my needs. So I tried to change the name “portfolio” into “my_name_of_custom_post_type”. Still no luck
I’m inserting the code into my theme’s function.php file
any idea on what’s wrong here ? Maybe it’s just a syntax problem ?

try one

function my_post_types($types) {
    $types[] = 'portfolio';
    return $types;
}

add_filter('s2_post_types', 'my_post_types');

try two

function my_post_types($types) {
    $types[] = 'portfolio';
    return $types;
}

add_filter('s2_post_types', 'portfolio');

(I’ve also checked via GD taxonomies plugin that the name I”m using are correct, and they are)

http://wordpress.org/extend/plugins/subscribe2/