Language estimation

Is there a way to guess, which language the user is using most likely ? e.g. browser or system preferences ?

http://stackoverflow.com/questions/2316 ... ip-address

[quote:1benkjue]

Please, PLEASE, do not make the mistake of thinking that IP == language. Look at the browsers accept-language header first, then the browser identification string which might contain the OS language, and only then take the IP into account. In almost 100% of all cases the browser accept-language header will be present and sufficient.

And always give the user the choice to switch to another language.

Just apart from the simple case of a foreigner abroad, how do you determine the language for Belgium, where they speak French, Dutch and German? (Maybe that doesn't apply to your case, but just philosophically. <img src="{SMILIES_PATH}/icon_e_smile.gif" alt=":)" title="Smile">).