Been trying around now a while, but it seems with trying I won't get any further

I need the follwing structure:
2 coloumns of which the left is split in two rows, the right one spans over these two.
The cells include HTML content with slideshows from WOWSlider.
Right now i only manage to build the structure without spanning the right one over the left two.
Does look like http://tm-dac.coffeecup.com/index.html, the right slideshow should span over the left two.
Originally the right slideshow is the same height as the two left ones so that it looks like a square picture made of three slideshows... I don't know why the right slideshow is shrinked.
Would be so happy if you could help me.
Thanks a lot
Thomas