Navbar dropdown toggle close on click (like in bootstrap default)

Hi,

I use Joomla 3.3 and a T3 BS3 based template. I'm trying to create a mainnav navbar with dropdowns that akts like bootstrap's default.
Means: I click on a dropdown-toggle and dropdown opens. I click again and dropdown closes. Exactly like http://getbootstrap.com/components/#navbar-default

I'm pretty close, but the "click to close" does not work yet.

What I did is:
- disable megamenu
- set dropdown toggle to: click
- create a main menu entry, type: External URL, href: #
- add sub entries to it

This creates following code:

   

      

         Startseite

      

      

         Über uns

            

               

                  Title

               

  ...

What am I missing to make the dropdown-toggle actually close the dropdown?


PS: now here's a copy of the live site on my dev box: http://dev.kuther.net/joomla/ -> the "Über uns" dropdown is the one I'm playing with