Bind error messages (DNSKEY)

[clemens at dwf.com]

I have recently started getting the following pair of error messages from bind:

        bg DNSKEY: please check the 'trusted-keys' for 'bg' in named.conf.: 6 
Time(s)
        bg DNSKEY: unable to find a DNSKEY which verifies the DNSKEY RRset and 
also matches one of specified trusted-keys for 'bg': 6 Time(s)

Anyone know what these mean, and what I am suposed to do?
-- 
                                        Reg.Clemens
                                        reg at dwf.com