Mapping for bilingual sites

[Rickyhow]

Current Situation
I have a website that I need to provide in two languages, English and French. So I created two websites and link the related pages (i.e. the "Who We Are" page has a link to the "À propos de nous" and visa versa).
Site 1. /a/dar-rcd.com/dar/
Site 2. /a/dar-rcd.com/rcd/

I have successfully mapped site 1 to the domain www.dar-rcd.com (Web address www.dar-rcd.com Site Location: dar )

My Problem
I have not been able to map the french website to www.dar-rcd.com (Web address www.dar-rcd.com Site Location: rcd )

What am I doing wrong?

Thanks kindly,
-Richard