theme settings api

Hey Guys I am having trouble getting my primary links to be a.active when I am on a child page of that parent menu item. After searching drupal.org until I was blue in the face I thought this would be a great little check box in the theme settings for zen since I need this on a lot of sites I build. What do you guys think? Do you all have any other ideas about theme settings that would make our lives just a little easier?

Thanks to all those who have helped with zen it really rocks!