I have no idea how. I've checked this with Ebay and Paypal by email, and spoke to a Paypal support bod on the phone just before my last post. I've decided to go to NOCHEX, even on their website they show a comparison between themselves and Paypal/Worldpay, the comparison indicates that for CC's registration is required with Paypal.
You obviously have some exclusive functionality, I'd keep it quiet if I were you :)
/edit
Are the customers making the payments in the US?