Seems to be okay on 5.8.4/AS810 with DBM::Deep v0.94.

P:\test>test2
$VAR1 = \bless( {
   'TASK_QUEUE' => bless( {
        'DEV' => bless( [
              bless( {
               'FILE' => 'bar1',
               'CMD' => 'foo1'
             }, 'DBM::Deep' ),
              bless( {
               'FILE' => 'bar2',
               'CMD' => 'foo2'
             }, 'DBM::Deep' )
            ], 'DBM::Deep' )
      }, 'DBM::Deep' )
 }, 'DBM::Deep' );
$VAR1 = \bless( {
       'FILE' => 'bar1',
       'CMD' => 'foo1'
     }, 'DBM::Deep' );
$VAR1 = \bless( {
   'TASK_QUEUE' => bless( {
        'DEV' => bless( [
              bless( {
                       'FILE' => 'bar2',
                       'CMD' => 'foo2'
                     }, 'DBM::Deep' )
            ], 'DBM::Deep' )
      }, 'DBM::Deep' )
 }, 'DBM::Deep' );
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P:\test>perl -V
Summary of my perl5 (revision 5 version 8 subversion 4) configuration:
  Platform:
    osname=MSWin32, osvers=4.0, archname=MSWin32-x86-multi-thread
[SNIP]  
  Locally applied patches:
        ActivePerl Build 810
        22751 Update to Test.pm 1.25
        21540 Fix backward-compatibility issues in if.pm
  Built under MSWin32
  Compiled at Jun  1 2004 11:52:21
  @INC:
    c:/Perl/lib
    c:/Perl/site/lib
    .

P:\test>perl -MDBM::Deep -e" print $DBM::Deep::VERSION"
0.94
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