I have been using RH 6.0 for about 6 months on this machine. I's been running great. about a weeks ago, i lost the use of 'finger' and 'who'. Well the binaries still work.. but they say that no one is logged in, even though I've got, say 4 sessions open.
Both the /var/run/utmp and /var/log/wtmp are their, and being written to.