Multisite and WPML, all for sub domains?

Hello,

I have a multisite WordPress setup with the following sub domains defined:

Main network: clientsite.com
Blog site: blog.clientsite.com
Knowledge site: support.clientsite.com

The two subdomains are individual sites from a WP MU install. All is OK and good up to this point.

I would like to add WPML to translate the site but instead of having /fr at the end, I would like a different subdomain like so:

blog.clientsite.com -> blogue.clientsite.com (in French instead of blog.clientsite.com/fr)
support.clientsite.com -> soutien.clientsite.com (in French instead of support.clientsite.com/fr)
clientsite.com -> fr.clientsite.com (in French instead of clientsite.com/fr)

On the WPML forms, I see this solution that does not seem to work even after installing Sunrise. When I go back to WPML Language tab, I cannot select sub domains.

Questions:
1) Do I need to setup WPML before Multisite?
2) Anybody achieve something like that before? It must not be the first time this arises?
3) Any way to do it with Apache URL Rewrite instead ?

Any help will be welcomed!
Thanks!!