AAAA and DDNS A Records coexist

[John Ruff]

dhcp-3.0.3_1
bind-9.3.2

It seems that I cannot have a static AAAA record and have DDNS update  
with a A record when the host name is the same.  With an existing  
AAAA record for 'bob' dhcp will fail adding the DDNS A record for  
'bob'.  Is this expected behavior?  If so, I assume dhcp is checking  
for an existing A record with the same IP or Name as the one it's  
attempting to add.  But it's not taking into consideration the record  
type.  I would think adding a A record for 'bob' is fine if 'bob'  
only exist with a AAAA record.  Any way to make this work?

The DDNS update work fine if I remove the AAAA record.

Regards.