#!/usr/local/bin/perl -l -w

use strict;
use Storable;
use Data::Dumper;

package MyPack;

sub new {
 my $class = shift;
 bless {attrib=>"red"}, $class;
}

sub STORABLE_freeze {
 my ($self, $cloning) = @_;
 return if $cloning;

 return $self;
}

# $self always seems to be an empty object
# blessed into the class, so lets re-bless it.
sub STORABLE_thaw {
 my ($self, $cloning) = @_;
 return if $cloning;

 bless $self, 'NoPackage';
 $self->{mykey} = "value";
 return $self;
}

package main;

my $obj = MyPack->new;
my $thing = { a=>"abc", b=>$obj };
print Dumper($thing);

store $thing, 'store.tmp';

my $another_thing = retrieve('store.tmp');
print Dumper($another_thing);

Output:
$VAR1 = {
          'a' => 'abc',
          'b' => bless( {
                          'attrib' => 'red'
                        }, 'MyPack' )
        };

$VAR1 = {
          'a' => 'abc',
          'b' => bless( {
                          'mykey' => 'value'
                        }, 'NoPackage' )
        };
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When Storable comes across a reference blessed into a class, it examines that class to see if there is a 'STORABLE_freeze' method (and _thaw, I guess, but that's out of the scope of this question) that can produce a "serialized" version of that object. If it exists, according to the documentation for Storable, it's to return a serialized version of the object. If no such method exists (or if the first invocation of this method returns an empty list), Storable reverts to what it normally does.

I am just attempting to define a STORABLE_freeze method for the DBI database handle (which seems to be of the DBI::db class, but I haven't been able to investigate past this point yet), which returns a garbage/no-op serialization for the database handle, much like what Storable does by default when you set $Storable::forgive_me and attempt to serialize a coderef or a file handle. Make sense?

Your code seems to work as-is, though, without error (though your _thaw routine is non-sensical from a Storable point of view, as it does nothing to restore the value that was saved, but that doesn't matter), so I'm wondering if I'm doing something wrong at a more fundamental level...