#!/usr/bin/perl

use strict;
use warnings;

use XML::LibXML;

{
   my $xml = <<'__XML__';
<?xml version="1.0"?>
<TOP>
  <SUB>
    <THIS>STUFF</THIS>
    <SOME.TYPE>T</SOME.TYPE>
    <SOME.OTHER.TYPE>BLAH</SOME.OTHER.TYPE>
  </SUB>
</TOP>
__XML__

   my $doc = XML::LibXML->new->parse_string($xml);

   for ($doc->findnodes('//*')) {
      my $name = $_->nodeName();
      $name =~ tr/.//d;
      $_->setNodeName($name);
   }

   print($doc->toString());
}