Reporting cpu utlization on linux using SNMP

I have a Liunux server with 4 CPUs running snmpd. I have configured
server monitor on Appmanager for the box. The cpu utlization reported by Appmanager looks incorrect. It is very high compared to what showing on the server using sar or top.
I have compared the result running JFFNMS and the cpu utlization reported by JFFNMS
iis much closer to SAR and top on the linux server. You can configure JFFNMS to
be aware of the multifple CPU on the box. E.g CPU utlization average 62%, the value
reported by top was 12% , that reported by SAR was 15%.

Is there a bug with Appmanager in the way it is interpreting the SNMP MIB?

The AppManager version we are running is AppManager 7, build 7300 Service Pack 3.0

Steven