The problem was named after an incident in 1996 in which AOL‘s profanity filter prevented residents of the town of Scunthorpe, North Lincolnshire, England from creating accounts with AOL, because the town’s name contains the substring cunt.
I didn’t know the name of this problem until today. I’ve definitely run into it on some basic profanity filters (early Jive products especially).
edit July 24, 2014: via http://www.inversoft.com/blog/2013/10/03/profanity-filter-build-vs-buy-analysis/