I tested the page in the same environment (Windows XP, IE8) but as you can see from the attached screenshot, I was not able to reproduce the problem. I also tested with different IE8 browser modes (IE8 compatibility view, standards view, quirks etc.) but still to no avail.
Do you get the same problem if you open the site from another machine? Also do you experience such problem in a real scenario, or you only see it on our demos? If you have an application where this issue could be reproduced, please send it to us and we will check it.
the Telerik team