Animation isn't showing shadows

[brodie]

I've got a big walkthrough that I'm doing with some shadows. When I export the animation, though, the shadows don't show up. Since the model is so detailed it takes several seconds for the shadows to show up when I orbit. So I think maybe when I create the .jpg's for the animation it's creating them before the shadows have a chance to generate perhaps? Anyone else have this issue or know of a fix?

-Brodie