Someone

 $dialog = Gtk2::Dialog->new; #('flv->mp3 converter');
 $dialog->set_title('flv->mp3 converter');
#  $dialog->signal_connect(delete_event => \&delete_event);
 $dialog->set_border_width(10);
 $box1 = Gtk2::HBox->new(FALSE, 0);
 $dialog->add($box1);
 $dialog->show;
 $box1->show;