Does rdate adjust the system clock or the hardware clock?
I understood vroom to mean that the system clock is fine (likely uses NTP client) but the underlying hardware clock drifted waaaay off. This would only be a problem after power-cycle.
I have the same problem with a Debian box. Sometime I'll get around to cron'ing this: hwclock --systohc, which should keep the hardware clock from drifting so far.
cheers,
ybiC