Updated field on hatom data

Hi

It’s Andres from Spain. I’m using Parabola 1.3.4 on AvionesMilitares

Checking the website with Google Webmaster Tools I get an error on every entry that tells that there is no ‘updated’ field on hatom-data. there is info about author, entry-title, entry-content, bookmark and tags, but gives this error:
Error: Missing required field “updated”.

You can check it here:

I have been playing and able to add the ‘updated’ touching single.php but that changes the presentation of Author, date of blog, ant category.

Could you add this info in order to avoid those stetics errors on Google WebMaster Tools?

Thank you