Send output to more than one e-mail id in customer

Hi Friends,

My business requirement is when we creates the invoice through RERAIV, the output should go to customer through mail.

one way of doing is select check box "Email" in RECPA520, but my business don't want to execute this manually. And through this process i can send output only to one emial id (standard) which is maintained in business partner master.

Is there any way to send mail to other mail-ids which are maintained in business partner?

If anybody had this scenario, pl advise.

Thanks in advance,

Srini