PHP - How to test $_SERVER['HTTP_ACCEPT_LANGUAGE']

I have a function that 开发者_JAVA百科can be used to redirect the user to different web pages based on the settings of $_SERVER['HTTP_ACCEPT_LANGUAGE'].

However, I cannot find a method with Firefox to test this code.

Firefox 3.6.8
Tools/Options/Advanced/Fonts
Fonts for // changed this part
Default Character Encoding // changed this part

However, the return results from $_SERVER['HTTP_ACCEPT_LANGUAGE'] is always as follows:

HTTP_ACCEPT_LANGUAGE: en-us,en;q=0.5

Anyone here knows what I should do?

Thank you

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Tools -> Options -> Content -> Languages.
You will see a list of languages. The higher the language is in the list, the higher priority it has.