I imported a whole blog I had in MT to a wordpress install. Everything looks great. The posts look exactly as they should and on the main page and post page it shows that the post has been added to the correct categories. But when I use wp_list_cats in my sidebar it only shows 3 categories. So I tured on the option to show all empty categories and now all my cats show, but they show that there is "0" entries in that category. Now if you click on any "empty category" you will see that they all have posts.
I'm sure this has something to do from importing, but is there an easy way to go back and fix it without recategorizing all my entries (and there is over 100, so I don't look forward to that).