Hi Thanks for your quick response. I am using Tk-MDI-0.2 for Perl which is available from CPAN.
I am sorry for not posting the sample code and here it is.

use strict;
use warnings;
use Tk;
use Tk::MDI;

my $mw = tkinit;
my $mdi = $mw->MDI(
        -style=>'win32',
        -background=>'gray');

        
my $child1 = $mdi->add;
my $text = $child1->Text->pack;
$text->insert('end',"A text widget");

my $child2 = $mdi->add(-titletext=>'Listbox Title');
my $mbar = $child2 -> Menu();
$child2 -> configure(-menu => $mbar);
my $submenu = $mbar -> cascade(-label=>"OPTIONS", -underline=>0, -tear
+off =>0);
$submenu -> command(-label => "FILE", -underline=>0);
$submenu -> command(-label => "EDIT", -underline=>0);
    
my $lb = $child2->Listbox->pack;
$lb->insert(0,"A Listbox");
 
MainLoop;
[download]

When I run the above code no error messages received but the menu will not appear in the child Window. Hope you Monks will help me in resolving this issue.