Dear Monks

I've been using popup menus for a while such as:

sub add_edit_popup
{
  my ($mw, $obj) = @_;
  my $menu = $mw->Menu(-tearoff=>0, -menuitems=>[
    [command=>'Start Term Info', -command=>[\&get_term_info_from_col_1
+_partial, $obj,]],
    '',
    [qw/command Copy/, -command=>['clipboardCopy', $obj,]],
    [qw/command Paste/, -command=>['clipboardPaste', $obj]],
    '',
    [command=>'Select All', -command=>[ 
      sub { $_[0]->selectionRange(0, 'end'); }, $obj, ]],
    [command=>'Unselect All', -command=>[ 
      sub { $_[0]->selectionClear; }, $obj, ]],
  ]);
  $obj->menu($menu);
  $obj->bind('<3>', ['PostPopupMenu', Ev('X'), Ev('Y'), ]);
  return $obj;
}
[download]

I'd like to add a menu entry wiht suboption. In a classical menu, I obtain this with a simple:

my $frame_GUI = $mw->toplevel;

my $menubar = $frame_GUI->Menu(-type => 'menubar');
$frame_GUI->configure(-menu => $menubar);

my     $menu_export_import = $menubar->cascade(-label => '~Import/Expo
+rt', -tearoff => 0);
my     $menu_export = $menu_export_import -> cascade(-label =>"Export/
+Print", -underline => 0, -tearoff => 0);
    $menu_export->command(-label => 'MS Word)',  -command => sub{expor
+t_word()});
    $menu_export->command(-label => "MS Excel)", -command => sub{expor
+t_html()});
my     $menu_import = $menu_export_import -> cascade(-label =>"Import"
+, -underline => 0, -tearoff => 0);
    $menu_import->command(-label => 'MS Word)',-command => sub{import_
+word()});
    $menu_import->command(-label => 'MS Excel', -command => sub{import
+_excel()});
[download]

How can use the same structure of menu/submenus in the popup code above?

Thanks