use strict;
use warnings;

my @list = ( '2005-12-01' , '2005-11-02' , '2005-12-07');

my @sorted = map  { $_->[3] }
             sort {
                     $a->[0] <=> $b->[0]  ||
                     $a->[1] <=> $b->[1]  ||
                     $a->[2] <=> $b->[2]
                  }
             map  {
                    [ 
                      unpack( 'A4 x[A] A2 x[A] A2', $_ ),
                      $_ 
                    ]
                  }
             @list;