cross-install needs C locale to work properly.
cross-install does not work properly if the locale is different than C,
because it considers every non-english dpkg message as "unusual", and
Either LANG=C (or LC_ALL=C) is added to cross-install, or else it should
not consider unusual messages as a fatal error.
Note: This is the reason boot/servers.boot.dpkg-new was not renamed to
boot/servers.boot last time I used cross-install. The reason I did not
notice there was indeed an error is that the unsual messages list was
so large that I missed the initial lines:
ERROR: dpkg did return unusual messages, please investigate: