NTP synchronization (System Setup -> Time) can be quite useful for synchronizing the time.  However, you will run into problems if you enable this feature in a virtual environment as it will not function correctly, and if you have it enabled on a virtual machine then you should disable it.

What can be done instead of using NTP in a virtual environment, is for us to add a script that will periodically synchronize the time. If you log a ticket with the SpamTitan Helpdesk then we can do this for you on request. 

If you are using VMware you can also install VMware Tools on your SpamTitan server and then configure the VM to synchronise it's clock with the host server.