Lifestyle theme sidebar problem in IE 7

Hello Everyone.

I have a problem with the revolution lifestyle theme.
It is about the right sidebar, it is in a wrong position..
I have removed the changes i made to the theme and put a clean lifestyle theme on it, but the result is the same..
The rightsidebar isnt displayed on the right, but just beneath the post/page…
Link to printscreen (clean theme):
https://img12.imageshack.us/img12/3416/lifestylethemeerror1.jpg

Link to the website (with my changes)
https://www.leukespreekbeurt.nl

Hope that someone can figure out whats wrong, cause it is driving me nuts..

Thanks so much!