From: "Gary Funck" <gary@intrepid.com>

If you're using Spamassassin, you can tell it which locales and languages
you expect,
http://spamassassin.apache.org/full/3.0.x/dist/doc/Mail_SpamAssassin_Conf.ht
ml

For example, this should catch most European (Latin) dialects:

ok_languages en fr it es de
ok_locales en

We place this sort of local configuration info. in local.cf along with
other driectives like trusted_networks, whitelists, and local overrides
of rule scores.