I'm running two sparc64 boxes on different versions of -current -- one a
V100 running 4.99.36 (updated rarely since it's my mail server, network
storage for the PCs, etc.) and a Netra T1 running 4.99.45.  Both point
at the same NTP server (an older NetBSD/i386 box that's peered to some
external NTP sources)...

The older box (running 4.99.36) keeps great time.. the newer box,
however, loses so much time it's about 40 seconds off now, and it hasn't
been up more than 1.5 days.

So, at least on sparc64, the CVS HEAD seems to keep pretty abysmally bad
time.  I haven't yet dug into any details but thought I'd send a query /
heads-up here.

--rafal