use strict;

use Safe;

my $CODE = << 'END';

package A;

sub new {
  my($class) = @_;
  print "hi there";
  bless { }, $class;
}

package B; 

@ISA = qw(ROOT::A);

END

# If I uncomment this line, everything works.
# eval $CODE;

my $safe = Safe->new('ROOT');

$safe->reval($CODE);       
warn "code - $@" if $@;

ROOT::B->new();
warn "new - $@" if $@;