Finally taking the plunge and started the migration from 11.1 to 11.2.3a.
The upgrade to 11.2 has gone smoothly for the primary servers and sats.

Now we are running the External Sybase database I can see this line in for 11.2.1 in the patch list
28 Jun 2012 - ZCM 11.2.1 - RPM to upgrade database to ZCM 11.2.1 when using external OEM Sybase on Linux

Is this required for the 11.2.3a upgrade as well ?