check-integrity complains while deleting MX record with no Arecord, but not while deleting.

[Jack Tavares]

>>  
>> However, when I try to delete this record with
>> update delete test.net.   500 IN MX 1 ddd.test.net.
>> I get 
>> update failed: REFUSED

>Problem is not missing A (or AAAA) record. It looks like you don't
>have permission to remove that record. You should look into named's
>log and try find why is update refused.

Nope. I have permission to delete it or any other record.
And I can delete it as soon as I add an A record.