The error is back! And this time none of the solutions I mentioned above work. Help!

(It's happening consistently on three different installations)

The line that produces the error is:
define('IMAGE_CC_ENABLED_VISA', zen_image($template->get_template_dir('cc1.gif', DIR_WS_TEMPLATE, $current_page_base,'images/icons'). '/' . 'cc1.gif'));