REQUIRE(rdataset->rdclass == db->rdclass) failed

[Maria Iano]

We have a private internal TLD which I have our resolver pull as a slave zone
to prevent it failing dnssec. It has subdomains and normally our
resolver follows the delegations and resolves those correctly without
needing to pull slave copies.

If I use the option:
attach-cache "globalcache";

and query a subdomain then named dies with the error:
general: critical: db.c:767: REQUIRE(rdataset->rdclass == db->rdclass) failed
general: critical: exiting (due to assertion failure)

So far my server is running fine once I remove 'attach-cache
"globalcache";'.

Is this a known issue with internal private TLDs and I should just give
up on using a shared cache? Getting rid of our internal domain is a huge
undertaking which won't be completed any time soon.

Thanks,
Maria
?