how to keep left-side-bar navigation bar collapsed ?

Hi,

Referring to latest wordpress package ; and a vertical menu

I want to have my main navigation panel on left ( within the left side bar ).

So I tried including a menu using the admin panel ( customise ) but my problem is all subpages under each link are always shown. The menu is always fully expanded.

What I want is only to expand the menu and show the subpages under specific link only when clicked.

Ex. when I click a main link in the navigation panel ( lets say ‘ about ‘ ), I want the sub links under that link to be shown/ expanded ( then it shows sub pages like ‘ about the company ‘ etc .)

Your help is appreciated !

Mebox Dileesha.