Hi, i have checked this, and the html tags are displaying correctly in product description (list view) as well as in the product page.
There is no fix needed for this, we fixed it a long time ago.
Be sure to have this lines:
<?php echo nl2br($_product->getShortDescription()) ?>
Also, in /app/design/frontend/default/hellomix_iphone/template/catalog/product/view/description.phtml
<?php echo nl2br($this->getProduct()->getDescription()) ?>