my %hash = ( name  => 'Ovid',
             color => [ 'red', 'blue' ],
             COBOL => 'sucks' );

##</code><code>##


while (($key, $value) = each %data) {
    $key = uri_escape( $key, $cgi_chars );
    foreach ( @$value ) {
        my $array_value = uri_escape( $_, $cgi_chars );
        $query_string .= "$key=$array_value&";
    }
}