package My::Apache::Session;
sub TIEHASH {
  my $class = shift;
  bless [@_], $class; # remember real args
}
sub FETCH {
  ## DO NOT USE shift HERE
  $_[0]->my_initialization;
  $_[0] = Apache::Session->TIEHASH(@{$_[0]});
  goto &{$_[0]->can("FETCH")};
}
sub STORE {
  ## DO NOT USE shift HERE
  $_[0]->my_initialization;
  $_[0] = Apache::Session->TIEHASH(@{$_[0]});
  goto &{$_[0]->can("STORE")};
}
sub my_initialization { ... }