APM Send Post Parameters to External Login Page

Hello That's what I meant when I said that I misunderstood the functionality of External Logon. I thought It was the way to call a full external Web Authentication App. I with try with HTTP AAA Object. But I have several doubts. I don't know if its possible to pass session vars as parameters with post. On the other hand, I'm using a grid card authentication system. So, it's not using user and password but user cell-1 value and cell-2 value. The captions for both vales change (C1, A2, J5, B8...). Regards.