Transaction Types in Order Management

Hello,

I have a business case that when I create a sales order and after shipping the items, i have to issue an RMA against that sales order.

When RMA is issued, there is another line which will be created for Re-stocking fee which is a positive amount. The restocking fee is a bill-only line.

When the RMA (which is a negative amount) and the restocking fee (which is a positive amount) are processed into Receivables, they create two transactions since each has its own transaction type.

The requirement is to have one transaction a credit memo with two lines (one positive and one negative) Is this possible to achieve?? Please advise.