I'm getting reports from users using IE 5.0 that with this hack the thread display doesn't start until after the bottom of the left column. So as you look down the page, they'll see the header, left column, then have to scroll down to the end of the left column to where the posts etc start.
For example: "I am using IE 5.0, Windoze NT 4.0 and having the same problem. The posts appear below the bottom of the sidebar on the left side of the screen."
Perhaps if the side bar was extended so that it filled up the entire left side, all the way down the bottom. I'm such an HTML idiot I'm not sure how to accomplish this...