use XML::Simple;

my $xml=<<'EOXML';
<config logdir="/var/log/foo/" debugfile="/tmp/foo.debug">
  <groups></groups>
  <age>18</age>
  <weight>220</weight>
  </config>
EOXML

my $xs  = XML::Simple->new;
my $ref = $xs->XMLin($xml);

use Data::Dumper;

warn Dumper($ref);