my $sharename = Encode::encode("UTF-16BE", $sharename_utf8);

##</code><code>##

sub hexdump {
    print join(" ", unpack("(H2)*", shift)), "\n";
}

use Encode;

my $sharename_utf8 = "\x{3042}";

my $sharename = encode("UTF-16BE", $sharename_utf8);

hexdump($sharename_utf8);   # e3 81 82
hexdump($sharename);        # 30 42