use strict;
use warnings;

use Unicode::Map();
use XML::Simple;

my $string = '<eleve nom="qsdqsd" prenom="Raphaël" classe="Seconde L" adresse="Léon Bourgain" code_postal="3423" ville="machin" pays="France" telephone="3421434" />';

# Convert to utf-16
my $map = new Unicode::Map("ISO-8859-1");
my $utf16 = $map->to_unicode($string);

# Recommended to call XMLin using 'eval', to trap errors
my $ref = eval { XMLin($utf16) };
$@ and die "An error occurred in XMLin:  '$@'\n";

# Now you can use '$ref' ...
my $out = XMLout($ref);
print "XMLout => '$out'\n";