You could use XML::Dumper instead...

use strict;
use warnings;
use CGI;
use Data::Dumper;
use XML::Dumper;

my $cgi = new CGI;
$cgi->{dummy} = new CGI;

my $serialized = pl2xml($cgi);
print "$serialized\n";

my $deserialized = xml2pl($serialized);
print Dumper($deserialized);
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And the output -

<perldata>
 <hashref blessed_package="CGI">
  <item key=".charset">ISO-8859-1</item>
  <item key=".fieldnames">
   <hashref>
   </hashref>
  </item>
  <item key=".parameters">
   <arrayref memory_address="0x1950ba0">
   </arrayref>
  </item>
  <item key="dummy">
   <hashref blessed_package="CGI">
    <item key=".charset">ISO-8859-1</item>
    <item key=".fieldnames">
     <hashref>
     </hashref>
    </item>
    <item key=".parameters">
     <arrayref memory_address="0x1ad737c">
     </arrayref>
    </item>
    <item key="escape">1</item>
   </hashref>
  </item>
  <item key="escape">1</item>
 </hashref>
</perldata>

$VAR1 = bless( {
                 '.parameters' => [],
                 '.charset' => 'ISO-8859-1',
                 'dummy' => bless( {
                                   '.parameters' => [],
                                   '.charset' => 'ISO-8859-1',
                                   '.fieldnames' => {},
                                   'escape' => '1'
                                 }, 'CGI' ),
                 '.fieldnames' => {},
                 'escape' => '1'
               }, 'CGI' );
[download]