Too bad that you can't use something like XML::Tidy. I tried it, and it returned this:

<?xml version="1.0" encoding="utf-8"?>
<config>
  <sites>
    <site>
      <sitename>www.example.com</sitename>
      <active>1</active>
      <rooturl>http://www.example.com.com/</rooturl>
      <name>Example</name>
    </site>
    <site>
      <sitename>Test entry</sitename>
      <name />
      <rooturl>http://www.test.com.com/</rooturl>
      <reportname>test report name</reportname>
    </site>
  </sites>
</config>
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The code that I used:

#!/usr/bin/perl

use strict;
use warnings;
use XML::Tidy;

my $tidy_obj = XML::Tidy->new(
               'filename' => '/path/to/xmlfile');
$tidy_obj->tidy();
$tidy_obj->write();
[download]