Without looking at your code, I would suggest not bothering too much about IE8 – it is heavily flawed and as it’s very much still in BETA, then it can’t be used as a test browser. Don’t test sites in IE8 for any reasons other than curiosity until a final non-beta version is released.
I agree about the IE 8 thing. We’ll all have plenty to worry about once it is actually released. Until then, it’s just BETA and I wouldn’t waste any time trying to fix bugs around it, as it will inevitably change.