reCaptcha failure allows checkout to progress stil

-- url of the page with the problem -- : iwddemo.com
-- HikaShop version -- : Business 2.2.1
-- Joomla version -- : 2.5.14
-- PHP version -- : 5.3.23
-- Browser(s) name and version -- : Firefox 23.0.1
-- Error-message(debug-mod must be tuned on) -- : Error_message

I'm trying to use the reCaptcha plugin that you provide. It seems to be half working. If I don't get the image correct, it allows me to proceed to the next step in the checkout process, however, it does give me the failure error at the top of the page. I would think that failing to pass the reCaptcha test wouldn't allow the checkout to progress.