my $ref = {thing => 'value', otherthing => 'other'};
%alias_to_ref = ;# insert magical code here
                 # to create a hash which will
                 # still modify $ref

$alias_to_ref{thing} = 'newvalue';

print $ref->{thing};

##</code><code>##

#!/usr/local/bin/perl -w
use strict;

my($ash) = {thing => 'other', and => 'antoher'};

my(%hash);

tie %hash, 'MyHash', $ash;

$hash{thing} = 'new';

print $ash->{thing}."\n";

package MyHash;
require Tie::Hash;
@MyHash::ISA = qw(Tie::StdHash);

sub STORE
{
	my $me = shift;
	my $key = shift;
	$me->{$key} = shift;
}

sub TIEHASH
{
	my $package = shift;
	my $ref = shift;
	return bless($ref, $package);
}