I couldn't wait longer so i bought another extension : www.sprinnet.com/magento/ajax-vat-number-validation
This one works perfectly, i had any problem to integrate it.

I want you to give my money back. Maybe it's only 9€ but i can't consider to pay something doesn't working.

Please inform me how you could do that.

Do you need something else ?

Dear Jich,

The steps you gave does not work. I check the frontend validation and the Javascript is correctly loaded in the header.
Here is what firebug returns me :

I've bought the VAT Checker extension and i've installed it propely like how your product details show to do :
- Downloading ID is ok.
- Log out/Log on was done.
- The validate-vat CSS class was added.

But all the VAT number i put in the corresponding field is rejected, even the good ones !

I've sent you severals emails but for now, i've received no reply !

I could read on another topic that you advice one of your customer which had the same problem than me to change module. If i had to do that, i will ask you first to give my money back, otherwise i will ask to Magento Connect to remove you from their store. I'm also going to the biggest european event on Magento in few days, i'm sure i will meet someone of the magento team.

Hope you will answer quickly to my demand.

Regards,

I don't think so... I'm trying to do the same thing... I'm following this tutorial : www.fontis.com.au/blog/magento/automatic...gento-customer-group and for now, i can't see if it's working until Vat checker extension see as a valid vat number a valid vat number and none as a not valid one :-( !!