Need Advice for Building a Payment Module: Secure Token / Embedded Iframe / PCI Comp.

I've got a client that wishes to use their obscure payment gateway that offers an embeddable checkout form. Someone here is I'm sure familiar with it, I'd think it's fairly standard these days: you first, on the server, send a request (with a unique id and some initial transaction data) to a gateway server using curl or whatever, and the gateway sends you back a secure token. You then use that token to embed and iframe and then send the client an embedded iframe that has a form requesting card data.

This is a way to ensure PCI Compliance.

Are there any modules in zencart that use this method, that maybe I could read the source code to get an idea of how it works to build a custom payment module?

Anyone?

Am hoping to make a recommendation this week.

Thanks!

Check out the CREsecure payment module. It may be here or on their site (cresecure.com). The thing I don't like about it is that there's the payment page where you choose "CREsecure" for payment, then after the order is confirmed, it goes to the secure hosted payment form. This is not how customers are used to shopping on the internet (payment, then confirm is usual). But it might give you something to go on.

I'm integrating CREsecure hosted payment page and it's a lot of custom coding unfortunately...you can't do it with just a payment module if you want it to work as checkout does now.