Hi,

the bug you describe seems to appear on windows only. It can be boiled down to the following example.
Also this workaround is a bit more 'general-purpose' as it does not require the widget to be managed by the 'pack' geometry manager:

use strict;
use warnings;
use Tk;
use Tk::Text;

my $mw   = tkinit;
my $t    = $mw->Scrolled('Text',
                         -scrollbars => 'osoe',
                     )->pack;
$t->update;
$t->insert("insert", sprintf "%3d.  Text Text Text\n",$_) for(0..64);
$t->update;

# force scrollbar refresh:
# my $sb = $t->Subwidget('yscrollbar');
# $sb->set( $sb->get );

MainLoop;
[download]

Cheers, Christoph