Gtk::Label::set_text() doesn't grok international characters?

["Federico Heinz" <fheinz vialibre org ar>]

I've just stumbled upon a very strange thing... if $lbl is a
Gtk::label, and I tell it to $lbl->set_text("child"), it works
great, but if I tell it to $lbl->set_text("niño¨), it doesn't
change $lbl's text. Same goes for $lbl->set(). Am I missing
something here?

        Federico Heinz