How to authenticate a user in SSL page

Hello all,

I'm using forms authentication for my website and I want the user to
be authenticated in a HTTPS page. Also, I created a members area (a
SSL virtual directory) and I want to allow the user to get in and out
of the members area with the same login.

Can anyone help me on how to do this? My problem is that I can't
configure the members subdirectory as a <location> in web.config
because I would have to specify the absolute URL (because it's https://...).
On the other hand if I configure the members subdir as a separate
application the login isn't shared.

Thanks in advance,

Manuel Ricca