# Support RFC 3066 language tags, which use '-' instead of '_'.
    $name =~ tr/-/_/;

    my $key = $name;

    return $LoadCache{$key} if exists $LoadCache{$key};

    # Custom class registered by user
    if ( $Class{$name} )
    {
        return $LoadCache{$key} = $class->_load_class_from_id( $name, $Class{$name} )
    }

    # special case for backwards compatibility with DT::Language
    $name = $OldAliases{$name} if exists $OldAliases{$name};

    if ( exists $DataForID{$name} || exists $AliasToID{$name} )
    {
        return $LoadCache{$key} = $class->_load_class_from_id($name);
    }

    foreach my $h ( \%NameToID, \%NativeNameToID )
    {
        return $LoadCache{$key} = $class->_load_class_from_id( $h->{$name} )
            if exists $h->{$name};
    }

    if ( my $id = $class->_guess_id($name) )
    {
        return $LoadCache{$key} = $class->_load_class_from_id($id);
    }

    die "Invalid locale name or id: $name\n";
}

sub _guess_id
{
    my $class = shift;
    my $name = shift;

    # Strip off charset for LC_* ids : en_GB.UTF-8 etc
    $name =~ s/\..*$//;

    my ($language, $script, $territory, $variant ) =
        parse_id($name);

    my @guesses;

    if ( defined $script )
    {
        my $guess = join '_', lc $language, ucfirst lc $script;

        push @guesses, $guess;

        $guess .= '_' . uc $territory if defined $territory;

        # version with script comes first
        unshift @guesses, $guess;
    }

    if ( defined $variant )
    {
        push @guesses,
            join '_', lc $language, uc $territory, uc $variant;
    }

    if ( defined $territory )
    {
        push @guesses,
            join '_', lc $language, uc $territory;
    }

    push @guesses, lc $language;

    foreach my $id (@guesses)
    {
        return $id
            if exists $DataForID{$id} || exists $AliasToID{$id};
    }
}

sub parse_id
{
    $_[0] =~ /([a-z]+)               # id
              (?: _([A-Z][a-z]+) )?  # script - Title Case - optional
              (?: _([A-Z]+) )?       # territory - ALL CAPS - optional
              (?: _([A-Z]+) )?       # variant - ALL CAPS - optional
             /x;

    return $1, $2, $3, $4;
}

sub _load_class_from_id
{
    my $class = shift;
    my $id = shift;
    my $real_class = shift;

    # We want the first alias for which there is data, even if it has
    # no corresponding .pm file.  There may be multiple levels of