lightbox not working in ie7, theme issue

Hi,
I’m using Lightbox on my blog. It works fine in firefox, chrome, safari, my wii browser (I think it is an opera browser). It doesn’t work in ie7 or ie8. The dark overlay only covers part of the webpage. I’m certain it is a theme issue, as I temporarily tried it with the default WP theme and it worked okay in ie7. However, I have no idea what is causing the problem in the theme I’m using right now (Fjords03). I would think it is a css issue but a few attempts to fix it failed.

http://www.dryfly.ca/blog