When creating more complex sites, for pages of posts and such it's useful to have this function be able to pass a page id as the current page when displaying.
I modified the function (actually replicated it so it won't collide with WP's original) and added $current_page to the default values for accepted $args. After all the function does set $current_page to 0 as initialization.
Afaik, it's not causing any breakage anywhere. I'll report if something wrong pops up.