error on line 2 at column 1: Extra content at the end of the document

Hi,

I have the following error:

This page contains the following errors:
error on line 2 at column 1: Extra content at the end of the document
Below is a rendering of the page up to the first error.
I am running wordpress 3.5 and wordpress seo 1.3.4.1.

I am using WPML version 2.6.1 (last version) and I am running 2 languages. I am using WordPress SEO because it should work fine with WPML, creating sitemaps per languages.

If I hide the 2nd language in WPML I don’t have the error, while if I enable the 2nd language, there is this error. I don’t have any idea to solve alone..Please Help!!

Thanks!

http://wordpress.org/extend/plugins/wordpress-seo/