BEFORE TO DOWNLOAD THIS CONTRIBUTION you MUST have the Anti Robot Registration Validation 2.5 Full Package - contact_us included!! released by Alex Studio on 5 Dec 2006
(link is http://www.oscommerce.com/community/contributions,1237)

I CANNOT garantee this will work with other version that this 2.5 by Alex Studio!!

This is a full package. If you have already installed previous version, just copy paste the contact_us.php from the archive to your shop.

This time the contribution IS working fine!!

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