Hello

Why you want to disable this message?

I have a suggestion for you. You take a look a Javascript in: app/design/frontend/rwd/default/template/catalog/product/view/type/options/configurable.phtml (rwd package)

 <script type="text/javascript">
        var spConfig = new Product.Config(<?php echo $_jsonConfig ?>);
 </script>

Here is two files js you should care:

js/varien/configurable.js

js/varien/product.js