erickn@isfe:/home/erickn> cat t
use warnings;

$hash{John} = '';
$hash{Bob} = '';
$hash{xavier} = '';
$hash{alice} = '';
for my $key (sort {ucfirst($b) cmp lcfirst($a)} keys %hash) {
   print "$key\n";
}


erickn@isfe:/home/erickn> perl t
alice
xavier
Bob
John