search for: ferret_syntax_chars

Is there any somewhat standard way to remove or otherwise handle special or syntax characters from a user''s search, such as a colon? I was thinking maybe there was something akin to Ferret::Analysis::FULL_ENGLISH_STOP_WORDS, like Ferret::Analysis::FERRET_SYNTAX_CHARS, but no such luck. How are other folks dealing with filtering user input? John