Menubar with other theme, hover effect issue

menu with other themes, hover not working .
For example using pepper-grinder theme , check this js fiddle http://jsfiddle.net/bababalcksheep/pKHTc/.
When Hover an item, item should be highlighted as white color as per theme which it does not.In above jsfiddle, I have placed both simple menu from ui and menubar to compare.

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