package IsaCGI;
use strict;
use CGI;
use vars qw(@ISA);
@ISA=qw(CGI);

sub my_method{
   return "hello from isa_cgi\n";
}

##</code><code>##

sub new {
  my($class,$initializer) = @_;
  my $self = {};
  bless $self,ref $class || $class || $DefaultClass;
  ...

##</code><code>##

my $q = new IsaCGI;