Fixed background image in IE with javascript

To fix a background image in the browser everybody uses background-attachment: fixed. However in IE this CSS property only works for the body tag while it works also for divs in Firefox and other browsers. So there must be a Javascript solution for IE. Please look at [login to view URL] in IE. The body tag holds the yellow lines so the grass was placed into a div as a fixed background image. For this page I used a script that I found at [login to view URL] but as you see the background image jumps when you scroll up and down. Using IE expressions in the stylesheet results in the same behaviour. I found another solution: Dean Edwards' IE7 javascript library ([login to view URL]). Using this script the background image doesn't jump but it sometimes completely disappears when the browser is resized. On the other hand the layout is messed up a little as soon as I link the library to the head section. Of course I could fix the CSS file but I don't want to fix a stylesheet that has worked before I added some Javascript classes. So what I need to be done by a Javascript expert: Take either the first one of these open source scripts ([login to view URL]) and fix it or write a new function. The script must work on IE 5.0, IE 5.5, IE 6.0 (Windows) and IE 5.2 (Mac).