(Update posted, see below)
As posted in multiple places around the web:
/etc/init.d/ntp stop date `date +"%m%d%H%M%C%y.%S"`
/etc/init.d/ntpd stop date `date +"%m%d%H%M%C%y.%S"`
This first manifested itself for us in our Java stacks — all of our (dual processor) Tomcat servers were running at a load of 30-40. However, this is a known (and fixed) kernel bug:
Apparently, simply forcing a reset of the date is enough to fix the problem:
date -s "`date`"