# IPC/Msg.pm lines 61-79
sub set {
    my $self = shift;
    my $ds;

    if(@_ == 1) {
        $ds = shift;
    }
    else {
        croak 'Bad arg count' if @_ % 2;
        my %arg = @_;
        my $ds = $self->stat
                or return undef;
        my($key,$val);
        $ds->$key($val)
            while(($key,$val) = each %arg);
    }

    msgctl($$self,IPC_SET,$ds->pack);
}

##</code><code>##

  my $ds = $self->stat

##</code><code>##

  $ds = $self->stat

##</code><code>##

  {
    package IPC::Msg::Bugfix;
    our @ISA = qw/ IPC::Msg /;
    sub set {
      # corrected version of set here ...
    }
  }
  # in your code
  my $msg = new IPC::Msg::Bugfix('24h', IPC_CREAT);
  # and continue as before

##</code><code>##

  # avoiding buggy multiple-arg set()
  # $msg->set('qbytes' => 32768); 
  my $ds = $msg->stat or die "stat: $!";
  $ds->qbytes(32768);
  $msg->set($ds);