Uninitialized string offset warnings in template variable $classes

When using jcarousel with views I get Notice: Uninitialized string offset warnings for line 11 of the includes/jcarousel-view.tpl.php file if the number of nodes the view is displaying is greater than 14.

The error is due to $classes[$id] being empty - prior to that it id displaying consecutive letters in the string "jcarousel-view" - which has 14 letters.

While this doesn't effect the carousel and the notices are not shown with warnings switched off - it'd be great to fix this as is a pain in developer mode and also googling "jcarousel notice: Uninitialized string offset" brings up other sites that have this displayed so some users probably don't realize it's showing?

This is the fix I've used which works:

<ul class="<?php print $jcarousel_classes; ?>">
    <?php foreach ($rows as $id => $row): ?>
        <?php if (isset($classes[$id])) {  ?>
            <li class="<?php print $classes[$id]; ?>"><?php print $row; ?></li>
        <?php } else { ?>
            <li><?php print $row; ?></li>
        <?php } ?>
    <?php endforeach; ?>
</ul>

Is there a need for the $classes[$id] to be added?