I think this problem may have something to do with the use of a the mainmenu module in the column. I have noticed that not collapsing by default only happens where there is a menu.
I am using a semi-effective CSS override to have menus in the left column collapse by default.:
#ja-container2 div.jamod ul.menu { display: none; }
#ja-container2 div.jamod ul.menu { display: block; }
In Firefox and IE, this causes the menu to collapse onpageload, so you still see the menu briefly at first. Not ideal, but okay until I find a better solution…
:confused:Interesting Note:
This collapsing issue has not ever seemed to be a problem in Google Chrome.