Add a Fancybox automatically to post type "post" images
<p>Currently, on <a href="http://www.seriouslyfish.com" rel="nofollow">my homepage</a> (which is a list of posts), if you click an image it opens in the same window as a full size image.</p>

<p>I'd like to change it so that when a user clicks said image it opens into a Fancybox pop-up.</p>

<p>I've got my Fancybox code, which works on my Custom Post Type pages (because I've been able to set the class/rel for these images):</p>

<pre><code>// fancybox
jQuery( document ).ready( function( $ ) {
    $("a img.fancybox").fancybox({
        'transitionIn'  :   'elastic',
        'transitionOut' :   'elastic',
        'speedIn'       :   600, 
        'speedOut'      :   200, 
        'overlayShow'   :   true,
        'overlayOpacity':   0.7,
        'overlayColor'  :   '#333',
        'titlePosition' :   'over'
    });
});
</code></pre>

<p>But I don't know how to add Fancybox to the code that WordPress automatically gives to its linked images in posts:</p>

<pre><code>&lt;div id="attachment_542" class="wp-caption alignleft" style="width: 135px"&gt;
    &lt;a href="http://www.xxx.com/wp-content/uploads/2011/12/Amazonas-English-1.jpg"&gt;
        &lt;img class="size-thumbnail wp-image-542 fancybox" title="Amazonas English" src="http://www.xxx.com/wp-content/uploads/2011/12/Amazonas-English-1-288x381.jpg" alt="Amazonas English" width="125" height="165"&gt;
    &lt;/a&gt;
    &lt;p class="wp-caption-text"&gt;Amazonas Magazine - now in English!&lt;/p&gt;
&lt;/div&gt;
</code></pre>

<p>Any suggestions? Is there a way I can do this using just the jQuery selector on Fancybox, or will I have to implement a WP filter to amend post-inserted image links so that they include a specific id/class?</p>

<p>Thanks in advance,</p>
