I need to make 3 level menu. Dropdown tabbed style menu.
The markup I get now is the default one:

<div menu-container>
   <ul level-one-menu>
      <li>
          <a>Dropdown</a>
          <ul level-two-menu>
             <li>
                <a></a>
             <ul level-three-menu></ul>
             </li>
         </ul> 
      </li>
   </ul>
</div>

And what I need is having submenus, level two and level three, outside of of level one menu.

How can I archive that?

Thanks in advance.