NoCat with Paypal

Hi All,

I am developing a service for WISPs where the wireless user would be
able to buy internet time after logging into the captive portal and
being authenticated. As I see it, the service will incorporate NoCat
and FreeRadius.

My question is: is it possible to use Paypal along with NoCat to
process both credit card and non-credit card payments . If I remember
correctly, I read somewhere on another site, that support for Paypal
had been considered, though I searched the archives but couldn't find
any post related to Paypal.