sub Tk::RotCanvas::meine_methode{
my $self = shift;
#tu was
}

package Tk::MyRotCanvas;
use warnings;
use strict;
use Tk::Derived;
use Tk::RotCanvas;

use vars qw( @ISA );
@ISA = qw( Tk::Derived Tk::RotCanvas );

Construct Tk::Widget 'MyRotCanvas'
sub ClassInit {
  my( $class, $parent ) = @_;
  $class->SUPER::ClassInit( parent );
}

sub Populate {
    my( $self, $args ) = @_;

    $self->SUPER::Populate( $args );
} 

# weitere methoden

1;