Hi - according to the sites I looked in, later releases of AIX V4.2.1 all have
a DPI V2 compliant snmpd built-in. You imply you are on AIX V4.3, so have you
actually checked whether you don't already have the correct level? The snmpd
component is in fileset bos.net.tcp.client so you might want to check you are
on the latest level here (which looks like either 4.3.1.2 or 4.3.0.5, depending
on your base level of AIX - you can download fixes from
http://198.17.57.66/aix.us/aixfixes?lang=english). If that still doesn't get
you the correct snmpd, then you are best opening a call with IBM AIX Support.
Hope this helps.

Regards,
Charlotte Brooks, IBM Australia, Systems Storage Division.
Email: cbrooks AT au1.ibm DOT com
Ph: 61-2-9353-3437