For some reason, I took a look at the "addons" my copy of IE8 had installed -- I wanted to sort them by date (to see which was oldest), but no matter how many times I clicked on the column header, they wouldn't seem to sort. Just then, I realized they were sorting, just not the way you would think.
We always knew addon support in IE was an afterthought, didn't we? Please tell me it's not supposed to be like that. (I used to have this problem as a budding Notes developer a LONG time ago, until I learned the difference between text and datetime formats.)