OAF - JDev 10.1.3 Is it possible to send HTTP header keys

Hi,

I have a custom OAF application built from where external users can view their invoices and pay. When they choose to pay, I navigate them to a third party payment site with few parameters like amount and ID etc as parameters as shown below.

String url = "https://xx.abcstage.com/CheckoutService/Payment/CurPay";
String compUrl = url+"?productId="+prodId+"&paymentAmount="+totamount.toString()+"UniqID="+ID; 
pageContext.setForwardURL(compUrl, null, OAWebBeanConstants.KEEP_MENU_CONTEXT, null, null,     
                    true, OAWebBeanConstants.ADD_BREAD_CRUMB_YES, OAWebBeanConstants.IGNORE_MESSAGES);

It was working fine for few years now. And we have a change of payment vendor now and they are insisting on sending a http header with a constant key in it.