XTRF does not exactly "support" languages like CAT tools do. It can use whatever you define as a language.
It makes use of pre-defined languages, which are used as parameters on quotes, projects, client and vendor rates. There is a list of default, built-in languages that come in every new XTRF deployment (+250 items). Authorized users can change it by editing, adding and removing languages.
Note that local varieties are treated as separate languages.
XTRF uses a set of standard parameters to make languages 'understood' by users, vendors and CAT tools it integrates with.
Languages are found and defined among System Values, as shown below.
Customer support service by UserEcho