Great way to spend a Saturday night. So much fuss about Y2K and turns out a single second can turn a simple night into chaos.
Simply put, here's a possible fix that might save the night:
/etc/init.d/ntp stop; date; date `date +"%m%d%H%M%C%y.%S"`; date
After doing this, see if the cpu usage falls down. If not, a simple restart of the service should be enough.
Edit: There are some advices about leaving ntp off for a while