Time Keepting In Virtual Environments (clock Drift, Etc...)

I have worked with VMWare quite a bit, and have found that no matter what tweaking you do a clock skew of up to a minute (relative to the host clock, itself kept accurate enough via NTP) is unavoidable at times, at least for a Linux 2.6.x based guest.

Do any of the common technologies allow guests to be kept more closely in sync with the host clock and so be more accurate (assuming the host's clock isn't wide of the mark, of course)? Do some of the technologies work OK with using NTPd to regulate the guest clock (under VMWare this is bad idea as it "conflicts" with VMWares own clock synchronisation method potentially making things worse than they otherwise would be).

The reason for the question is that I'm playing with some code that will run on a few different locations and while I can use an external source to fake a clock to the accuracy I want (+/- a second or two) most of the time, I wouldn't have to if I could rely on the VM's wall-clock being that accurate. If the project goes anywhere (my toy projects usually don't!) it would use real machines, but at this stage I'd rather avoid that expense/hassle.