Hi Joel, Thanks for your response. This is indeed a wierd one! In fact, my code is already doing what you suggest... the absolute path was expanded by php from Wordpress's bloginfo - I was showing you the code I saved from the page, not my original source code which already uses bloginfo.
I'm stumped... I simply can't imagine why this is only happening in IE and why a CSS path being relative vs absolute would make such a pronounced difference. I'm actually trying to figure out how to use a relative path to reference the CSS as a hack to resolve this, but whatever I do, Wordpress doesn't seem to be able to find my CSS unless I use the bloginfo thing, which seems to be causing the problem. I'm a total rookie in WordPress, so I'm way outta my league here... I've posted a question on the Wordpress blog without much luck. I'll keep trying... Let me know if you think of something. - John