Javascript problem

This problem only shows up only in IE. The script works fine in Firefox.
http://www.godunplugged.com

I’ve inserted the adsense code at top of sidebar. It displaces the sidebar content down the page below main body of page – only in IE.

I’ve tried calling the script externally but to no avail.

I”m not really worried about keeping the adsense code, but I’d really like to understand the mechanics of why this is happening for future reference.

If anyone has workarounds for this problem… any help wold be greatly appreciated.