$config{pane} = $mw->Scrolled(
    sticky => 'nw'
   -width => 50,
   -height => 50
)->pack();

for (1) {
   $counter++;
   $config{"pane".$counter} = $config{pane}->Label
      -text "Dieser text steht immer unten"
   )->pack;
   $config{pane}->see($config{"pane".$counter}, -anchor => 's');
}