Is it possible to post (or save session data on form submit) without Javascript?

[eluser]umbungo[/eluser]
I am trying to make my payment gateway 'transparent' to the end user, that is keep the URL within my domain and keep the page styled like the rest of the site.

The payment gateway requires specific variables to sent to it by POST method.

The page preceding it contains address info input by the user.. which i would like to be remembered.

So is there any way to remember the data (by sessions, or post) whilst posting the required stuff to the payment gateway (which i have loading in an i-frame previously containing the address inputs)... ooh; perhaps some (mis)use of the form validation???? [[edit.. thinking about it i would need to be performing the validation on their server, damn]]