Set language?

[eluser]donald.tbd[/eluser]
Hello,

Im craeting a multilanguge page, different languages are stored in a database and user can select between them. Selected language is kept in a session.
My question is that if a user comes on my webpage a language is not set at first. Where is the right place to check if the language is set and if not then assign the default language? Im currently doing that in MY_Controller (because i know it is loaded on every page) but it doesent seem the right place for that. Any other ideas?
The sure thing is that it has to be loaded every page because the user is not always coming to www.mysite.com, he might come directly to www.misite.com/contact or smtng.

Thanks,
donald