function googlecartBeforeAdd(item, index, newQuantity, opt_node) {
	var items = googlecart.getItems();
	var mysku = item.getSku();
	var totalqty = newQuantity;
	var maxqty = item.getMaxQuantity(); 
	
	for(var i = 0; i < items.length; ++i) {
		if(index == i) continue;
		
		if(items[i].getSku() == mysku) {
			totalqty += items[i].getQuantity();
		}
	}
	
	if(totalqty > maxqty) {
		var diff = maxqty - (totalqty - newQuantity);
		item.setQuantity(diff);
		
		if(typeof NotEnough == 'function') {
			NotEnough();
		}
		
		alert('We may not have enough stock of this item to fill your order. Please send an email to orders@pennyweights.com to verify availability. Reference item# ' + item.getSku());
		
		return false;
	}
	
	return true;
}