A quick gander of the doc seems to indicate that you could use tagBind to couple a script to any attempts to change the text, where the script would prevent this, possibly as simpy as by doing nothing.

Update: this looks less promising, though it still might be doable. However, you can combine ROText and Text Widgets.

#!/usr/bin/perl -w

use Tk;

my $mw = MainWindow->new();
my $tr = $mw->ROText(-borderwidth => 1, -height=>1);
$tr->pack();
$tr->insert('end', "\t\tReadonly:\n");
my $t = $mw->Text(-borderwidth => 1, -height=>1);
$t->pack();
MainLoop;
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Or you can put Label and Entry widgets into a Text widget, as shown in Mastering Perl/Tk

--Bob Niederman, http://bob-n.com