I have a problem with the css popup menu open list, I'm trying to navigate the keyboard, I mean the tab button, but the second level does not focus, here is an example: http://advidea.com/test/menu.html ,
I think this is similar to the one you are trying to achieve. I’d better review your code and try to check if I can fix it.
Now stay with this: http://jsfiddle.net/cfWpE/