CentOS - Sep 2007 - centos 5 and cpuspeed

In older version of centos there was cpuspeed -d running that controlled 
current speed.

In centos 5 it is set for on demand and cpuspeed is not running.

I can startup cpuspeed and send it a signal SIGUSR1 to go full speed. 
This works.

However, What is the correct or prefered method to control the cpuspeed 
in centos 5?

THere are times when I want to tell the machine to go full speed and 
other drop back.

THanks,

Jerry