How to set FREE SHIPPING for 1 product categroy?

Hi there. One of my clients has e-shop based on Zend Card. I have been asked to disable SHIPPING cost for one product category (or enable FREE SHIPPING for 1 category).

It seemed easy for me at first sight. But... Can you please give me any advice where to look? Is this option in admin itself? Is there a plugin for it? Or do I have to write a condition to the source code?

Thank you

The only way I know to do that is to edit each product in the category to make it a free shipping product. I don't know of a way to set a whole category to be free shipping. Sorry!

Is this always a setting where ALL Products in a Category get set to Free Shipping and ALL Products in a Category get set to NOT Free Shipping?

Will the Products in the Category ALWAYS have the same master_categories_id or, if using Linked Products, and a Product is in 3 Categories ... and I pick a Category with 10 Products and some are using this category as the master_categories_id and some are just Linked ... are they still to be set as Always Free Shipping YES/NO?

The idea is that there are a couple ways to identify a Category of Products when wanting to do a global change ...

One is by master_categories_id and the other is by the categories_id relationship in the products_to_categories table ...