'Next' Button on Image Popup in Product Listing

[cimran]

I am using VM 2, Please goto this link
http://jewelryinternet.com/index.php/earrings/14k-white-3-ct-tw-diamond-inside-outside-hinged-hoop-earrings-detail
When i click on the Additional Images, there is an arrow to scroll next image, but when i click on the Main Image; there is no such arrow to scroll next/additional images
I want help to configure this on main image as well

Best Regards!

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