How can I stop a zero priced item being added to the cart!

[jimijbob]

Hi all,

I have my products set up so they have a custom fields. The first field is a 'Please select size' with a price of £0.00. The price is only updated when a size is selected. How ever the product can still be added to the cart when at £0.00. I want to prevent this from happening. Is there a configuration that I am missing or do I have to hack!

Many thanks in advance of any help

[jimijbob]

Can Anyone please help with this? I'm guessing its a case of validating when add to cart is clicked either the final price or the default custom field.

Thanks

J