I assume you use Perl Tk, in this case you can use a Tk::StatusBar widget for the task.

Here is a tiny patch to fix a problem, I encountered, regarding 'systembuttonface':

--- lib/Tk/StatusBar.pm    2004-02-05 05:21:14.000000000 +0200
+++ lib/Tk/StatusBar.pm.new    2010-03-29 12:58:51.164978272 +0300
@@ -147,7 +147,6 @@
     my $n = $self->ProgressBar(
         -borderwidth    => $borderwidth,
         -width          => 17,
-        -troughcolor    => 'systembuttonface',
         %args,
     );
[download]

Update: How would I do it: :)

use strict;
use warnings;

use Tk;
use Tk::StatusBar;
use Tk::ToolBar;

my $mw = MainWindow->new;
$mw->geometry('200x80+10+20');
$mw->optionAdd('*Label.font' => '{MS Sans Serif} 8');

my $tb = $mw->ToolBar(qw/-movable 1 -side top/);

my $connected = 1;

$tb->ToolButton(
    -image   => 'actreload16',
    -tip     => 'back',
    -command => \&toggle_conn,
);

my $sb = $mw->StatusBar();

my $txtstatus = $sb->addLabel( -relief => 'flat' );

my $icostatus = $sb->addLabel(
    -width  => 20,
    -relief => 'raised',
    -anchor => 'center',
    -side   => 'right'
);

toggle_conn();

MainLoop();

sub toggle_conn {

    if ($connected) {
        $connected = 0;
        my $text = 'Disconnected';
        $icostatus->configure( -image => 'connectno16' );
        $txtstatus->configure(
            -foreground   => 'darkred',
            -textvariable => \$text,
        );
    }
    else {
        $connected = 1;
        my $text = 'Connected';
        $icostatus->configure( -image => 'connectyes16' );
        $txtstatus->configure(
            -foreground   => 'darkgreen',
            -textvariable => \$text,
        );
    }
}
[download]

Regards, Stefan