use strict;
use warnings;
use CGI::Pretty ":standard";
use XML::Simple;

if ( my %params = CGI::Vars() )
{
    $_ = [ split /\0/ ] for values %params;
    print header("application/xml"),
        XMLout(\%params);
}
else
{
    print header(),
        start_html(),
        h1("OHAI: I CAN HAZ HTML FORMZ?"),
        start_form();

    print p(textfield("birthday")) for 1 .. 5;

    print end_form(),
        end_html();
}

__END__

perl pm-1019080 'birthday=1:356;birthday=2:365'
Content-Type: application/xml; charset=ISO-8859-1

<opt>
  <birthday>1:356</birthday>
  <birthday>2:365</birthday>
</opt>