If you have problem with Fontis Recaptcha Magento Extension like below, read.

Invalid method Fontis_Recaptcha_Block_Review_Form::escapeHtml(Array
(
 [0] => Rating
)
)

Problem is that some of the methods in template are using non existing method. This only happend on product review form page.

edit app/design/frontend/default/default/template/fontis/recaptcha/form.phtml

Replace: 

$this->escapeHtml(

with

$this->htmlEscape(

That’s it