How to configure rails app on non default port 443

I have a situation where i need to run name based virtual hosts in
apache as I only have one IP address, but have a couple of rails sites.
I have configured both successfully apart from the ssl side of things.
Now i know that ssl cant be used with name based hosts so I am trying to
configure one of my apps to use the non default ssl port so not 443 but
to use 8443.

The rails app though keeps sending traffic through to port 443 so I am
presuming this is a default. Is there a way to configure ssl to use a
different port, i am using ssl_required plugin.