Special navigation bar behavior
 

Hello, does anybody have an idea how I could implement an effect (like seen on the webpage http://www.jnj.com/connect/) in atahualpa 3.5.3 and wp 3.0.1.
I would like to have the submenus pointing out with a transparent background and this background should span over the full lenght of navigation bar (currently 990px). My current website is www.servvar.ch
Any inputs would be greatly appreciated.
Thanks in advance, Oliver