Warning: Please include a link to the DD script in question in your post, in this case, Image Thumbnail Viewer II. See this thread for the proper posting format when asking a question.
Try the following modified .js file, and then modify the markup for your thumbnails per the below example:
Code:
<a href="http://google.com" data-src="http://www.nasa.gov/images/content/167040main_image_feature_738_ys_4.jpg" rel="enlargeimage" rev="targetdiv:loadarea" title="The Universe is just waiting to be explored">Saturn #1</a><br />
In other words, change your thumbnails' markup so they use the new "data-src" attribute to specify the full path to the enlarged image (instead of "href" as was the case before), and use the "href" attribute instead to set the link the browser should go to when the user clicks on the thumbnail link.
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