I installed this for a client but the return url from Pinterest was not working. It was encoded wrong. Others have posted with the same problem.

Here is the fix. Edit tpl_modules_pin_it_button.php

Replace the following starting at line 27:

<div id="pinitButton" style="display: inline-block; vertical-align: top;">
<a href="http://pinterest.com/pin/create/button/?url=<?php echo urlencode($piniturl); ?>&description=<?php echo urlencode($pinit_name); ?>&media=<?php echo urlencode($pinit_image); ?>" id="PinItButton" class="pin-it-button" count-layout="<?php echo PINTEREST_BUTTON_COUNT; ?>">Pin It</a>


with this:

<?php
$piniturl = urlencode($piniturl);
$piniturl = str_replace('amp%3B', '', $piniturl);
?>
<div id="pinitButton" style="display: inline-block; vertical-align: top;">
<a href="http://pinterest.com/pin/create/button/?url=<?php echo $piniturl; ?>&description=<?php echo urlencode($pinit_name); ?>&media=<?php echo urlencode($pinit_image); ?>" id="PinItButton" class="pin-it-button" count-layout="<?php echo PINTEREST_BUTTON_COUNT; ?>">Pin It</a>