Category display in the post editor

Is there any way, like a plugin or something, that allows you to go to 3 levels of subcategories in the category display box in the post editor?

We have a lot of categories, with 2 uber-categories. One of them has only one level of sub-category, and that is displaying fine, hierarchically. But the other uber-category has 2 levels of sub-category and they are not displaying hierarchically, which is making it really hard to find the categories we need to select. Anyone have any suggestions of something that might help?