Thank you for your response. I passed this information to the Jreviews support and they said:
""We have several clients using JReviews with GTranslate without problems. All ajax responses that return a json object already have the Content-Type header set to application/json. You can clearly see that on your site using Firebug http://screencast.com/t/Dsjcvn309
That is the response from the call to generate the captcha and the Content-Type is correct. If you are having this problem then maybe your GTranslate version is out of date or they introduced a bug recently or something else on the site is causing the problem. Please have them check the page and the ajax response when you click on the add review button or the submit button in the review form. ""
Maybe there is a problem elsewhere or in the Gtranslate code? Thank you for your time.