Where to setlocale(3)?

How does one PROPERLY set the locale under which PHP scripts run? Is it a script level property, PHP level property, HTTP level property or inherited from the OS default? I have a module that converts strings between the locale character encoding and another encoding. Currently setlocale(LC_CTYPE, NULL) within a script returns 'C' which is to say the locale is not set. Where do I look? Thanks, Mike -- Michael B Allen PHP Active Directory SSO http://www.ioplex.com/