You have multiple hashes, so you need to tie all of them. I think that will work. You're just using autovivification to create them in the above script. Try something like this: 
use lib qw( . );
use MultiHash;

my %hash_a;
my %hash_b;

tie %hash_a, "MultiHash";
tie %hash_b, "MultiHash";

$hash{ x } = \%hash_b;
$hash{ x }{ y } = 10;
$hash{ x }{ y };

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In reply to Re: My code (I can't figure out how to implicitly recurse) by perrin
in thread How to tie multilevel (multidimensional) hash? by mikezone

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