Plugin having trouble to post comment successfully

Hello,
I am trying to add the plugin to a new website.

When I am trying to post a comment, the plugin stops at “Posting comment, please wait”. When I reload, the comment did post.
Here is the console from Chrome:

[WP-Ajaxify-Comments] Initializing version 0.6.1 wp-ajaxify-comments.js:68
[WP-Ajaxify-Comments] Found jQuery version '1.7.2' wp-ajaxify-comments.js:68
[WP-Ajaxify-Comments] Found jQuery blockUI version '2.42' wp-ajaxify-comments.js:68
[WP-Ajaxify-Comments] Search comment form (selector: '#commentform')... Found: [
<form action=​"http:​/​/​www.vistoimages.com/​wp-comments-post.php" method=​"post" id=​"commentform">​…​</form>​
] wp-ajaxify-comments.js:68
[WP-Ajaxify-Comments] Search comments container (selector: '#comments')... Found: [
<div id=​"comments">​…​</div>​
] wp-ajaxify-comments.js:68
[WP-Ajaxify-Comments] Search respond container (selector: '#respond')... Found: [
<div id=​"respond">​…​</div>​
] wp-ajaxify-comments.js:68
[WP-Ajaxify-Comments] Initialization completed wp-ajaxify-comments.js:68
Object
 chrome-extension://ipfnecmlncaiipncipkgijboddcdmego/scripts/track.js:24
[WP-Ajaxify-Comments] Comment has been posted wp-ajaxify-comments.js:68
[WP-Ajaxify-Comments] Found comment URL 'null' in X-WPAC-URL header. wp-ajaxify-comments.js:68
Uncaught TypeError: Cannot read property '1' of null

You can test the issue here: http://www.vistoimages.com/2012/07/16/hello-world/

I am also using Ajaxify WordPress Site plugin, but even if I desactivate it, it does not work too so I don’t think it is the issue.

Thank you for your time and help!

http://ww.wp.xz.cn/extend/plugins/wp-ajaxify-comments/