You have an interesting system dictionary then. None of the copies I checked (OS X, Open- and FreeBSD, Redhat 9 and RHEL3) contained any matches for grep -c fuc.er, and three innocuous ones for grep -c fuc. (Confucian, Confucianism, Confucius). I'd be more worried that a random hex hash might come up a55b00b5, but the truly paranoid would of course sanitize their wordlist to start.
Update: Wow, I did not know that. I just grabbed the source wordlist for the FC words-3.0.9 RPM and it indeed does work blue. Caveat emptor.