How to handle Multiple Merchant Account for the same Gateway

How to set up and use iPayment to handle multiple authorize.net accounts in SAP B1.

Is this possible and if so how to do it?

What i am seeing is there is only scope for adding only one Authorize.Net Profile in the Gateway configuration. How do we add multiple auth.net profiles?

Adding more details to the subject:

1) The cutomer has 2 Authorize.net accounts linked to 2 separate bank accounts, one for USD and the other for CAD.
2) Can iPayment support 2 Authorize.net accounts and if not, is there a workaround?
3) Can we have maybe some kind of automated backend update to switch API credentials when doing automated authorisation or settlement runs?
4) How do other iPayment users handle this multi currency/ Multi Merchant account scenario?