Filtering spam in national language

[cmon]

I work in an italian company, we are receiving some spam written in (very bad) italian language, obviously produced by some automatic translator.
Although their content is heavily pornographic, the spam score is very low, because they don't match any of the porn-specific rules, which are designed only for english language.
Does anybody know how can we extend the basic rules to add support for italian language pornografic spam?

Thanks, Carlo