Tweet button js not function on IE, all version


I’ve got a problem with the Tweet share button on my site.
I’m using the button generated from your site and I’ve embed the code in the page.

The code is :


The button was right for long but from a couple of days not function.

I know that the site that embed the button isn’t the best site in the world in term of js or efficiency, but I want to know the origin of the problem.
This is an example URL :

I have also test the code above in a blank page and with IE I’have problem too …

Can you help me?