A side note, just in case working things out with 'locale' would turn out to be impossible/too difficult/unportable.

I found two modules on CPAN that both seem to offer alternatives worthwhile to be considered:

No::Sort and Cz::Sort look just like an invitation to add Lt::Sort :), providing help for sorts in Norwegian and Czech, whereas Sort::ArbBiLex seem to be a more general solution for getting sort behaving as you want.

Hope that helps.