Importing data model from a custom RFC

Hi,

I have a custom RFC which has a importing parameter sales order number and returing a table consists of the sales order item details.

When I am trying to import data model from above custom RFC, it is creating two entity types. And it is allow me to create a different entity sets based on entity types. When I am trying to map to data source to RFC, there is no provision for mapping the importing parameters of custom RFC.

Is there any other way to achieve successful import data model and map to data source to RFC which has import and export parameters?

Thanks,

Suresh.