Yes, I assumed it was a bug. Manually changed it in the LEDCart_PHP.php oage and that has worked, thank you.
Thing is though, as mentioned above, the customer can still add the item to cart and even go right through to checkout and, one assumes, pay!?
Is there any way to prevent it being added to cart? Considering what happens if an item isn't available and the "Currently Unavailable" message is displayed, as part of the price lookup ajax function, is there any way to do the same if the price lookup ajax function returns a 0?