package Super;

sub method {
    # handle dual nature methods
    my $class = ref( $_[0]) || $_[0];
    print "In package: ", __PACKAGE__, 
          " called from $class\n";
}

package Sub;

use vars qw( @ISA);
@ISA= qw( Super);

sub new { bless {}; }

package main;

my $sub = &Sub::new();

$sub->method();
Sub->method();