Iframe make it clickable through and image
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I'm a publisher for an ad network I would like to know if it's possible to make the iframe clickable trough an image, so when some one click on it, the link that the ad network put on the iframe show up like a pop-under, like if some one has clicked on it... 
I tried with: <span></span> or <div></div> but the image is not clickable...