Various language variants considered as one language

Dear All,

is there any setting in XTRF that would make the system considered language variants of one language being the same language actually? We now have for example EN, EN-US, EN-GB variants but in general they all mean English. Still, if the vendor registers only one of the variants, they are not listed as a potential linguists for a job with different variant. This makes the process bit clumsy. Is there a way to fix it?

Thank you