[Plugin: WP e-Commerce] Facebook Like button not displaying correct image

I am trying to add a Facebook Like button to all of my products with the correct product image fore each. I understand almost all Facebook Like plugins allow you to set a default image for the og:image content, but I want to have a unique image for each product instead of the same image for all of them.

I tried adding the following to the header.php file as referenced from http://yoast.com/facebook-share-wordpress/

<?php
global $wpsc_query;
if ( $wpsc_query->is_single ) {
  echo '<meta property="og:title"
    content="'.wpsc_the_product_title().'" />';
  echo '<meta property="og:description"
    content="'.strip_tags(wpsc_the_product_description()).'" />';
  echo '<meta property="og:image"
    content="'.wpsc_the_product_thumbnail().'" />';
}
?>

I’ve had no luck with this however. Any help would be greatly appreciated. Not sure if this will help, but here is the beta page I am trying to fix before launching on the real site: http://beta.corpitus.com/?wpsc-product=test1

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