We've now implemented this using Extended Menu -
de.siteof.de/extended-menu.html
As noted elsewhere, the standard of documentation is appaling and you'll want to re-write all the CSS as the examples are 'basic' to say the least, but you can implement what was mentioned above using multiple instances of the menu module.
It includes the ability to 'split' at a specified level within the hierarchy, and can have different style sheets defined for the different areas of menus. To install this on most of the RocketTheme modules, you need to specify 'module' in the menu settings at the top of the template HTML page, then set your main Extended Menu module to appear in the 'Toolbar' module position.
Hope that helps.
Hi Thanks for your post. I tired that, but my problem is that I cant see any "Toolbar" poistion in my template, which is Media Mogul template. please help me.