dnssec-keygen: a key with algorithm 'HMAC-MD5' cannot be a zone key

[blrmaani]

I used to successfully generate keys when I have BIND 9.2 installed on
my host using the following
commandline

# dnssec-keygen -a HMAC-MD5 -b 128 -n ZONE mykey-otherkey

I upgraded my host to with BIND 9.3 and used the same command line
above to get the following
error:

# dnssec-keygen -a HMAC-MD5 -b 128 -n ZONE mykey-otherkey

dnssec-keygen: a key with algorithm 'HMAC-MD5' cannot be a zone key

What exactly changed? What is the alternative? If I use HOST instead
of ZONE what impact will it
have on the generated keys?

I can't downgrade to BIND 9.2 just to make the above work. Also I
can't have BIND 9.2 and BIND 9.3 both
on my host.

All my script may require change. But please let me know the side
effect?

thanks
Blr