Multiple HttpPost method in MVC4

Multiple HttpPost method in MVC4

In my web application I have a form where user can send SMS to any phone.
Because it is a form and have a submit button the function is declared
something like this. [HttpPost] public ActionResult Index(Massages
massages) { // called the webservice return View(massages); }
This works fine There is web service which sends the SMS message to
participant client (phone). In this web service call we also have to
provide PostBackUrl, so we could see the response which client has
provided.
This response is coming in form of JSON and HttpPost. I am puzzled how
declare such function.
//It is wrong but It might be something like this.
[HttpPost]
public ActionResult ReplyBack(JSON reply)
{
return View(reply);
}
Any help will be very much appreciated.
Best regards Agha Khan