As long as we're playing the "Falsehoods Programmers Believe About Names" game again, here's the relevant patio11 article: http://www.kalzumeus.com/2010/06/17/falsehoods-programmers-b... If you try to validate names, or if you don't safely escape names along with your other user-input strings, you're gonna have a bad time.
My name fail to register surprisingly often, even here in Brazil. It is Hélder Maurício Gomes Ferreira Filho Common reasons for failure is being too long and having non ASCII characters, but sometimes it fails for other reasons, for example do not allow me to register without a middle name ( I don't haven't one actually... ), me confused and not knowing how to register Filho ( it is not a family name, neither a surna…
Accented vowels are ASCII characters but in the extended set which people sometimes don't take account.