Rejecting naked_ip_address

I have noticed most of the emails I receive with naked ip addresses in the
HELP command are using my ip address! Since these are obviously forged
(confirmed by the MAIL FROM command), I would like to reject HELO commands
with a naked ip address (after suitable warn_if_reject trial). I do not
use the permit_naked_ip_address so that must be the default? I found a
thread from about six months ago but was unable to determine the solution
I am looking for.

Is there a simple Postfix specification like reject_naked_ip_address?

If not, other suggestions?

Oh yes, OS is SuSE 9.2 and Postfix version is 2.1.5 installed from SuSE
media.

Thank you,
Lucky Leavell