crisrocks

I'm getting the following error when I try to add something to the wishlist:
Fatal error: Call to a member function add_wishlist() on a non-object in /path/wishlist.php on line 19
 
Line 19 is this:
$wishList->add_wishlist($wishlist_id, $attributes_id);
 
I've tried the navigation_history fix, and other fixes on this thread. I need to get it fixed ASAP. Any ideas?