CPU utilization for certain user

[fajarpri]

Hi all,
I'm using Zabbix 1.4.5 on Centos 5.0.

Can I create an Item to monitor CPU utilization for certain user? Such as 'root'.
I try this:

Description: CPU Util Root
Type: Zabbix Agent
Key: system.cpu.util[,root]
Type: Numeric Integer64
Unit: blank
Use Multiplier: Do not use
Update interval: 5
Store value: As is
Show value: As is

Is it possible?
Thanks