Default language

Hi, i have a problem  to select the default language. From the admin pannel>language setting : i select the language i want to be by default and i save it.

I refresh the page and i can se is change.. But when i open my site still in English !! (ok, i can change with the flag.. ).

I try to clean the cache of the browser (safari 4 and ff), but nothing change...

Where i make a meastake in something simple like that !!!

Thank to all

maby also delete teh browsers cookies..

I try it... i empty the cache, i delete the cookie, i quit the application.... but nothing...

What i see is it remeber the last language i select... that's all...