"Allow Checkout" not working

[keress]

I'm trying to set the stock options so that when there are zero items in stock, the "allow checkout" option, set to "false" will halt the process.

 

I have the following options set:

 

Check stock level: true

Subtract stock: false

Allow Checkout: false

Mark product out of stock: Call for freight

Stock Re-order level: 0

 

How can I get this feature to work right? Right now, even though there are zero items of a product in stock the checkout process still proceeds.