I think this is one of those times you are falling foul of the Unicode problem. If you are using anything before Perl 5.8, you'll need to use the utf8 module (1)
(1) http://search.cpan.org/~nwclark/perl-5.8.6/lib/utf8.pm
If you're able to upgrade to 5.8.4 or higher, then the Unicode support is...