Can the submenu be shown constantly when clicked on a menu-item?

Hi there,
I notice that some people have trouble with using the ‘subsubmenu’ (third level menu item). When you move your mouse over the sub(sub)menu it’s there, but when you make the smallest movement outside the area of this menu, it dissapears. How do we get the sub(sub)menu to show itself continually, when somebody has clicked on the main menu of sub menu item? So that its visibilty won’t be dependent on the mouse hovering?
You can see what I mean on your demo under Portfolio (with sub and subsubmenu).
Thanks!
Daphne

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