There is currently a problem with the obscenity flter. Some "good" words have been flagged as "bad" and will be hidden. In order to correctly see the chat, you'l have to disable the obscenity filter. To do that, go to the Interface settings (Esc Menu -> Interface) and uncheck the "Obscenity filter" checkbox.
Is it going to be sanely language-specific? I remember the hysterical messages you'd see in RoM (French-language server and French-language clients for all participants in these messages) when someone was late for something. He'd say that he was late, and you'd see that he swore at everyone.
Why?
In French, "I'm late" is "Je suis en
retard" - this word is perfectly normal in French, and not obscene at all. But we'd just see "Je suis en ------" because retard is an insult in English... Oh yes, and there were the obscene discussions about cellars, which use, in French, the plainly obscene word, "cave" (means "cellar"). I, a native English speaker, could not explain this one to my guildies. I eventually found that "cave" is an obscure English-language synonym for "vagina".

It's not even common in English - why strike it out in French?
And last night in Allods I found people saying "lfg *** dps ***" ???? So I switched the filter off. FFS guys, how hard is it to pass a typical stream of genuine world-chat through the filter before releasing it?