http://devnulled.com/content/2004/08/how-to-set-the-system-clock-in-freebsd-and-keep-it-updated
The date is in YYMMDDHHMM format, the clock being a 24 hour and not 12 hour clock. Use the date command as follows:
bash-2.05b# date 0611161115
to get November 11, 2006 11:15 pm.