The installation guide should probably put some more emphasis on the instructions to set the /etc/localtime link and (if appropriate) set the time zone options in /etc/rc.conf BEFORE the first boot of the system. Otherwise, after the first boot, /etc/adjtime will have unreasonably large values in it, and will cause an unexplained major clock drift after several reboots. Also, it should probably be mentioned somewhere (the FAQ maybe?) that if you're having a large, unexplained clock drift, you probably did this and need to reset your /etc/adjtime file.
Fixed in the 1.4 install doc. //ZhEN
