is it possible to checkout with Credit card and bank Account in SandBox mode?

[hrn2k1]

Hi
is it possible to checkout with credit card provided by SandBox Test Account ?
I have one business test account (Website Payment Pro merchant a/c) and sandbox gives me API Credentials [API Username,API Password,Signature] I configure VirtueMart payment Method API ps_paypal_api with these credentials and Credit Card payment method type.

But when I checkout with credit card there shows an error after clicking Confirm Order button. error code-10501 This transaction cannot be processed due to an invalid merchant configuration

I see in API error list that its said - Occurs when the billing agreement is disabled or inactive.
Now how can I active the billing agreement for SandBox test Account?
is it credit card payment only for real credit card ? not for sandbox test account credit card?

please help me to fix the error.

...hArUn