I just tried to implement the drop down menu code from the jQuery: Novice to Ninja book and found a bug.
If you click on an item in the submenu of the drop down and then click on your browser's back button, the drop down is still in the down position and wont go away until you hover the mouse over the menu again. Strangely, the menu works fine in Chrome and IE7/8 but not in Firefox or Safari.
I have put an example up here: Jquery Menu
Thanks in advance.