Switching contents language in CodeIgniter

[eluser]KeyStroke[/eluser]
Hi,

I'm going to use CI's language class to make a site that supports English and Arabic. I have two questions about that though:

1) How do you usually separate both versions of the site?

for example: is it like ar.yourdomain.com/home (ar = Arabic), or yourdomain.com/ar/home? or maybe another way?




2) How do you swap languages within the application? Do you set a global language variable in each PHP file or a bunch of IF statements throughout the program or how exactly?


You help is much appreciated