The issue I am having can be demonstrated here:

http://www.jeasyui.com/tutorial/mb/menubutton_demo.html

The problem occurs when the window height is so small that the drop down from the menu will not fit inside the window.  What happens is the drop down then becomes a 'drop up' menu.  Basically instead of listing the options down the page it starts at the bottom and lists the menu options up. 

My question is can this functionality be changed so that it always drops down?  If so where in the code can this be altered?

Any help on this would be great.
Thanks