default language on spellchecker

Hi all

I have the following configuration:

FCKConfig.SpellChecker   = 'WSC' ;

this is working fine and when SpellChecker pops up it shows by default "American English".

How can i change the default language to "British English" ?

i have tryied to add

FCKConfig.wsc_lang    = 'en_GB' ;

i seen this somewhere on the internet, but still not working.

Any ideas?

Thanks

Rui