Sorry if this has been posted already. My search didn't find anything.

I've got a product set up that uses attributes. Instead of showing 'SOLD OUT' in the drop down list on the product details page when an item is out of stock, I'd like to not show that item at all in the drop down list.

Is there a setting for this in the Admin section? If not, can someone let me know how I can add an additional filter to the query that's used to build the drop down list items?

Thanks in advance for your help.