How can I create a horizontal menu?

Hi,

I'm using the built-in menu control using web.sitemap XML file but I'm not able to get a horizontal menu like the one below:

Home || Human Resouces || Information Technology || Marketing

The built-in menu wants to put all these departments under Home, like so:

Home
     Human Resources
     Information Technology
     Marketing

Basically, I want to have sibling nodes at the root level. Is this not possible with the built-in menu control?
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