ActiveMerchant and PayPal FLow pro

Hello guys,
As far as I’ve seen, there is still no “official” SDK (from paypal) for
ruby to access Paypal FLow pro accounts.
I’ve registered for PayPal Flow pro, and got the following items:
partner id,merchant ID and password.
I’ve tried to use Active Merchant, but when I try to create a
PayflowGateway Object, it seems to expect a login name and a password,
i’ve tried to create a User (in paypal manager) but it still doesn’t
work… any ideas ?
( I get an Invalid vendor account (StandardError) )

Thanks in advance,