It is actually! I've got an absolutely ancient PCMCIA wifi card that only supports 802.11b, but that's enough to connect to wifi and sync with NTP servers. Without it, the time drift is really bad, about 5-10 minutes/month.
I'm always amazed how bad time drift is with non NTP synced systems. I have a couple very inexpensive Timex Quartz analog watches that manage a month without any drift that I notice (they get reset when I need to reset the date wheel).
