Moving the displaced sov unit, and thus replacing the icon where it should be, allows secondary units to exit where the sov was...
Screen (was): http://screencast.com/t/NzU0YjdhYTk
However, any time you try to exit a unit into the sov stack (now replaced) the secondary unit exits on top of the city and not randomly ejected as before.
They are selectable on the city square.
Screen (on city square): http://screencast.com/t/YzQ4YjM0YTYt