ASP.NET Datalist - How to mouse over an image button (A) and the same image will display in Image button B

Hi,
I would like to create a datalist that has 4 images. 
The first image always change when user mouse over to any of the three images.
Something like this but the below links is for when you click.
http://www.showponyfashion.com/north-dresses-party-dress/nightingale-in-navy
Any help is appreciated.

Many Thanks,

Jeannie
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