package A;                 
	sub foo { print "called A::foo\n"; shift->NEXT::UNSEEN::foo() }

	package B;                 
	sub foo { print "called B::foo\n"; shift->NEXT::UNSEEN::foo() }

	package C; 
    use vars qw( @ISA );
	@ISA = qw( A );
	sub foo { print "called C::foo\n"; shift->NEXT::UNSEEN::foo() }

	package D; 
    use vars qw( @ISA );
	@ISA = qw(A B);
	sub foo { print "called D::foo\n"; shift->NEXT::UNSEEN::foo() }

	package E; 
    use vars qw( @ISA );
	@ISA = qw(C D);
	#sub foo { print "called E::foo\n"; shift->NEXT::UNSEEN::foo() }

package ::;

E->foo();