Why trouble to identify the exact words? I think it would be simpler to just have the regex identify obfuscated text, without worrying about exactly what the word is. Look for bizarre arrangements, caps in the wrong places, digits in the words, etc. Maybe keep a list of words that are OK (such as Win98), or (say) module names.

I would also suggest using a whitelist to identify messages from people you know, and pass them along without further processing. It would save you a bit of time, and also make subsequent testing more effective. People you know might use some suspicious words. Strangers should probably not be using obscenities or mentioning body parts in their first message... so it would be OK to filter strongly on those messages.