Invoice Interface to Oracle Receivables

The invoice processing in Order Management  collate the orders and returns for the creation of invoices and credit memos to recognize revenue and manage sales credits.  It say's that it can be  transferred to Receivable module by implementing WORKFLOW ACTIVITY(INVOICE INTERFACE). Is this seeded in the applications and something that I can run or this is something that need to be customize by developers?. I would appreciate if you can give me some information on this process.