Add custom fields to directory search manually

Hi Alessandro,
On your 2.0 WP User Manager release blog post you mention that the code is in place for adding custom fields to the directory search, but the UI is not finished yet. Could you provide some pointers for adding the custom fields manually? I see the wp_wpum_search_fields table. Is adding the custom field key there all that is needed or are there more steps?
Thanks!
Peter Shackelford