CSS Menu – Hover for Sub Menu

I am building a menu from wp_list_pages which displays more that the first layer of pages (using depth=2). What I want is that when you hover over the top level pages the child pages display to the right. This I have managed here:

http://clients.equaldesign.co.uk/limits/de/?page_id=14

However you will see that if you hover over page two the sub menu two disappears before you can get to click on it. How do I make it stay there until another link is hovered over?

Thanks in anticipation.