Hey there, I have an Arabic contact script that uses Ajax to retrieve a response from the server after filling the form.
On some apache servers, jQuery.parseJS
You should try using json2.js (it's on https://github.com/douglascrockford/JSON-js)
Even John Resig (creator of jQuery) says you should:
This version of JSON.js is highly recommended. If you're still using the old version, please please upgrade (this one, undoubtedly, cause less issues than the previous one).
http://ejohn.org/blog/the-state-of-json/