Payment processing gateways

[Spartakus]

Hello PHP Freaks,

I'm currently building a site for a company that will need bidirectionnal payment processing -- that is, clients will need to be able to make payments to the company (traditionnal stuff), but the company will also make payments to its clients (and not necessarily the sames ones that previously made payments to the company). I've been looking at doing this the usual way, i.e. using a payment gateway to receive and process payments made by customers. The catch lies in implemeting the other part of the process: a service like Paypal, for example, could allow the company to transfer money to individuals, but as far as I can tell there's no public API to automate the process. Ideally we'd like to find some kind of gateway that can be used to process payments [b]from[/b] a merchant account [b]to[/b] the customers' credit cards or bank accounts.

One option I've found so far is Neteller (not posting a link as I don't want this to come off as advertisement, just google the name if you're curious). The company would only be half satisfied by this solution, for reasons of their own. So I was wondering if someone here knows of another service that provides this. Preferably, it would have to be based in Canada, or at least be legally registered here, because that's also where my client is registered.

Thanks in advance.