use Net::LDAP::LDIF;
our $old_ldif = Net::LDAP::LDIF->new( "dump.ldif", "r", onerror => 'undef' );
our $new_ldif = Net::LDAP::LDIF->new( "dump_new.ldif", "w", onerror => 'undef', wrap => 76, encode => 'base64' );
while (not $old_ldif->eof()) {
    my $entry = $old_ldif->read_entry();
    if ($old_ldif->error()) {
        warn "Error msg: ", $old_ldif->error(), "\n";
        warn "Error lines:\n", $old_ldif->error_lines(), "\n";
    } else {
        # delete attributes no longer needed
        foreach my $a ($entry->attributes()) {
            if ($a =~ /^attrMatch/) {
                $entry->delete($a);
            }
        }
        $new_ldif->write_entry($entry);
    }
}
$old_ldif->done();
$new_ldif->done();