I have this sidepanel vertical navigation wherein sub-menus are displayed when hovered on a menu. My problem is that the sub-menus and children of the sub-menus are not being showing due to the div container.

Since the div container [side-panel-links] has a width of 240px, it is cutting it off. If you extend the width of the div container, then you'll see the sub-menus being displayed.

How could I possibly let the sub-menus overlap the div container to show these submenus?

Here's the demo : http://jsfiddle.net/xkBZE/5/