Wrong Menu Parent Stays Open

When I click on a Menu Item after I have already selected a Sub-menu Item from a different Menu Item, the new Menu Item does not stay open but the old Menu Item does.

www.mediaworksweb.com/dev/lenertz-cms

Example: Under Browse Products, click on Corrugated Boxes, then Stock & Custom Sizes - works ok. Then click on Bags - you'll see that the old Menu stays open, not the new one.

I fixed this by changing the Hidden Menu (Item for Category Listing) parameters to:

Type of layout: Div (Instead of List)