I do a lot of domain-specific stuff for dealing with configurations.
Your new friend is called $_SERVER['SERVER_NAME'] :)
I parse that to pick out the part of the domain name I need to load
the correct configuration.
You can do the same and use that to load the correct user profile.
I would try
Hello
In my cake app, each user has their own "profile" page, which is
http://www.example.com/users/profile/{user-name}
When user's join my website, I want to give them the ability to attach
a domain name to their "profile" if they choose. So for "user-a", a
visitor who goes to http://www.user-a
