I'm working on a public website that was built using SharePoint (WSS). We need to add an area in the site where people will be able to purchase items with their credit cards and obviously the area needs to be secured.

The website is using Form Based Authentication and the users need to stay logged in when they are moved back and forth from the https zone.

I know how to enable SSL for a new web application / site collection but this isn't really an option for me as the website is already online and we don't want the whole thing to be secured.

I am comfortable with the development of the webparts involved (payment module, shopping cart, etc.) but I can't really figure out how to create only certain https pages when the site collection is created.

Can you have features that deploy pages that are secured? If so, how? Can you have a zone where SSL is enabled but where the users are redirected to and from without losing their authentication (FBA)?

Thanks!