I don't know if Compiere have supported Online Payment Service completely yet?
Do we need a thirdparty for the service?
as far as I know there's only the VerisignPayflow Pro implemented as online payment service.
To use this you need at least a bank account in the USA and a contract with an acquirer (someone doing the credit card stuff for you).
For the european market we will offer a solution shortly but here's also a contract with an acquierer needed.
Please feel free to get in touch with me if you need any further information.
info <at> evoconcept.de