use XML::DOM;

 my $parser = new XML::DOM::Parser;
 my $xmlstring="<?xml version='1\.0'?>
<ACTION>
<INPUT LABEL=\"Radio Button\"/>
<INPUT LABEL=\"été\"/>
<RADIO ID=\"List\">
éééàààùùù</RADIO>
</ACTION>";
 my $doc;
 eval {
   $doc = $parser->parse($xmlstring);
 };
 if ($@) {
  die "ERROR : $@\n";
 } 
 print $doc->toString;