From LedHed's Wiki
FreeBSD's Clock will drift out of sync very rapidly when it is run as a guest OS on VMWare.
To resolve this issue do the following:
edit /boot/loader.conf and add this line
kern.hz="100"
Reboot the VM and set the date. The clock should stay roughly in sync.
You can also edit the Guest VM's .vmx file and setting this value:
tools.syncTime = "FALSE"