If you use a not english msgid in a rails ERB template, for example: _('Jelszó megerősítés'). And then you run rake gettext:find
it will likely raise an error like this:
rake aborted!
"\xC3" from ASCII-8BIT to UTF-8
~/.rvm/gems/ruby-1.9.2-p0@rails3/gems/gettext-2.1.0/lib/gettext/tools/rgettext.rb:198:in `write'