I can't find a single reference that state that it's possible without involving the serverside.
MSDN on:
- navigator.browserLanguage
- navigator.systemLanguage
- navigator.userLanguage
From browserLanguage:
In Microsoft Internet Explorer 4.0 and
earlier, the browserLanguage property
reflects the language of the installed
browser's user interface. For example,
if you install a Japanese version of
Windows Internet Explorer on an
English operating system,
browserLanguage would be ja.
In Internet Explorer 5 and later,
however, the browserLanguage property
reflects the language of the operating
system regardless of the installed
language version of Internet Explorer.
However, if Microsoft Windows 2000
MultiLanguage version is installed,
the browserLanguage property indicates
the language set in the operating
system's current menus and dialogs, as
found in the Regional Options of the
Control Panel. For example, if you
install a Japanese version of Internet
Explorer 5 on an English (United
Kingdom) operating system,
browserLanguage would be en-gb. If you
install Windows 2000 MultiLanguage
version and set the language of the
menus and dialogs to French,
browserLanguage would be fr, even
though you have a Japanese version of
Internet Explorer.
Note This property does not indicate
the language or languages set by the
user in Language Preferences, located
in the Internet Options dialog box.
Furthermore, it looks like browserLanguage is deprecated cause IE8 doesn't list it
