580022 - Invalid request parameter: amount must be greater than zero

HELP! I have a multisite and traffic coming through this one site. It all seems to be working fine on the other stores but for some reason it is not working for this store. When I go to checkout I get the following error. I am using chained paypal payments.
on http://www.grounds2give.com
580022 - Invalid request parameter: amount must be greater than zero